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SYSUTILS.INT
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{*******************************************************}
{ }
{ Borland Delphi Runtime Library }
{ System Utilities Unit }
{ }
{ Copyright (C) 1995,99 Inprise Corporation }
{ }
{*******************************************************}
unit SysUtils;
{$H+}
interface
uses Windows, SysConst;
const
{ File open modes }
fmOpenRead = $0000;
fmOpenWrite = $0001;
fmOpenReadWrite = $0002;
fmShareCompat = $0000;
fmShareExclusive = $0010;
fmShareDenyWrite = $0020;
fmShareDenyRead = $0030;
fmShareDenyNone = $0040;
{ File attribute constants }
faReadOnly = $00000001;
faHidden = $00000002;
faSysFile = $00000004;
faVolumeID = $00000008;
faDirectory = $00000010;
faArchive = $00000020;
faAnyFile = $0000003F;
{ File mode magic numbers }
fmClosed = $D7B0;
fmInput = $D7B1;
fmOutput = $D7B2;
fmInOut = $D7B3;
{ Seconds and milliseconds per day }
SecsPerDay = 24 * 60 * 60;
MSecsPerDay = SecsPerDay * 1000;
{ Days between 1/1/0001 and 12/31/1899 }
DateDelta = 693594;
type
{ Standard Character set type }
TSysCharSet = set of Char;
{ Set access to an integer }
TIntegerSet = set of 0..SizeOf(Integer) * 8 - 1;
{ Type conversion records }
WordRec = packed record
Lo, Hi: Byte;
end;
LongRec = packed record
Lo, Hi: Word;
end;
Int64Rec = packed record
Lo, Hi: DWORD;
end;
TMethod = record
Code, Data: Pointer;
end;
{ General arrays }
PByteArray = ^TByteArray;
TByteArray = array[0..32767] of Byte;
PWordArray = ^TWordArray;
TWordArray = array[0..16383] of Word;
{ Generic procedure pointer }
TProcedure = procedure;
{ Generic filename type }
TFileName = type string;
{ Search record used by FindFirst, FindNext, and FindClose }
TSearchRec = record
Time: Integer;
Size: Integer;
Attr: Integer;
Name: TFileName;
ExcludeAttr: Integer;
FindHandle: THandle;
FindData: TWin32FindData;
end;
{ Typed-file and untyped-file record }
TFileRec = packed record (* must match the size the compiler generates: 332 bytes *)
Handle: Integer;
Mode: Integer;
RecSize: Cardinal;
Private: array[1..28] of Byte;
UserData: array[1..32] of Byte;
Name: array[0..259] of Char;
end;
{ Text file record structure used for Text files }
PTextBuf = ^TTextBuf;
TTextBuf = array[0..127] of Char;
TTextRec = packed record (* must match the size the compiler generates: 460 bytes *)
Handle: Integer;
Mode: Integer;
BufSize: Cardinal;
BufPos: Cardinal;
BufEnd: Cardinal;
BufPtr: PChar;
OpenFunc: Pointer;
InOutFunc: Pointer;
FlushFunc: Pointer;
CloseFunc: Pointer;
UserData: array[1..32] of Byte;
Name: array[0..259] of Char;
Buffer: TTextBuf;
end;
{ FloatToText, FloatToTextFmt, TextToFloat, and FloatToDecimal type codes }
TFloatValue = (fvExtended, fvCurrency);
{ FloatToText format codes }
TFloatFormat = (ffGeneral, ffExponent, ffFixed, ffNumber, ffCurrency);
{ FloatToDecimal result record }
TFloatRec = packed record
Exponent: Smallint;
Negative: Boolean;
Digits: array[0..20] of Char;
end;
{ Date and time record }
TTimeStamp = record
Time: Integer; { Number of milliseconds since midnight }
Date: Integer; { One plus number of days since 1/1/0001 }
end;
{ MultiByte Character Set (MBCS) byte type }
TMbcsByteType = (mbSingleByte, mbLeadByte, mbTrailByte);
{ System Locale information record }
TSysLocale = packed record
DefaultLCID: LCID;
PriLangID: LANGID;
SubLangID: LANGID;
FarEast: Boolean;
MiddleEast: Boolean;
end;
{ This is used by TLanguages }
TLangRec = packed record
FName: string;
FLCID: LCID;
FExt: string;
end;
{ This stores the langauges that the system supports }
TLanguages = class
public
constructor Create;
function IndexOf(ID: LCID): Integer;
property Count: Integer;
property Name[Index: Integer]: string;
property NameFromLocaleID[ID: LCID]: string;
property NameFromLCID[const ID: string]: string;
property ID[Index: Integer]: string;
property LocaleID[Index: Integer]: LCID;
property Ext[Index: Integer]: string;
end;
{ Exceptions }
Exception = class(TObject)
public
constructor Create(const Msg: string);
constructor CreateFmt(const Msg: string; const Args: array of const);
constructor CreateRes(Ident: Integer); overload;
constructor CreateRes(ResStringRec: PResStringRec); overload;
constructor CreateResFmt(Ident: Integer; const Args: array of const); overload;
constructor CreateResFmt(ResStringRec: PResStringRec; const Args: array of const); overload;
constructor CreateHelp(const Msg: string; AHelpContext: Integer);
constructor CreateFmtHelp(const Msg: string; const Args: array of const;
AHelpContext: Integer);
constructor CreateResHelp(Ident: Integer; AHelpContext: Integer); overload;
constructor CreateResHelp(ResStringRec: PResStringRec; AHelpContext: Integer); overload;
constructor CreateResFmtHelp(ResStringRec: PResStringRec; const Args: array of const;
AHelpContext: Integer); overload;
constructor CreateResFmtHelp(Ident: Integer; const Args: array of const;
AHelpContext: Integer); overload;
property HelpContext: Integer;
property Message: string;
end;
ExceptClass = class of Exception;
EAbort = class(Exception);
EHeapException = class(Exception)
public
procedure FreeInstance; override;
end;
EOutOfMemory = class(EHeapException);
EInOutError = class(Exception)
public
ErrorCode: Integer;
end;
EExternal = class(Exception)
public
ExceptionRecord: PExceptionRecord;
end;
EExternalException = class(EExternal);
EIntError = class(EExternal);
EDivByZero = class(EIntError);
ERangeError = class(EIntError);
EIntOverflow = class(EIntError);
EMathError = class(EExternal);
EInvalidOp = class(EMathError);
EZeroDivide = class(EMathError);
EOverflow = class(EMathError);
EUnderflow = class(EMathError);
EInvalidPointer = class(EHeapException);
EInvalidCast = class(Exception);
EConvertError = class(Exception);
EAccessViolation = class(EExternal);
EPrivilege = class(EExternal);
EStackOverflow = class(EExternal);
EControlC = class(EExternal);
EVariantError = class(Exception);
EPropReadOnly = class(Exception);
EPropWriteOnly = class(Exception);
EAssertionFailed = class(Exception);
EAbstractError = class(Exception);
EIntfCastError = class(Exception);
EInvalidContainer = class(Exception);
EInvalidInsert = class(Exception);
EPackageError = class(Exception);
EWin32Error = class(Exception)
public
ErrorCode: DWORD;
end;
ESafecallException = class(Exception);
var
{ Empty string and null string pointer. These constants are provided for
backwards compatibility only. }
EmptyStr: string = '';
NullStr: PString = @EmptyStr;
{ Win32 platform identifier. This will be one of the following values:
VER_PLATFORM_WIN32s
VER_PLATFORM_WIN32_WINDOWS
VER_PLATFORM_WIN32_NT
See WINDOWS.PAS for the numerical values. }
Win32Platform: Integer = 0;
{ Win32 OS version information -
see TOSVersionInfo.dwMajorVersion/dwMinorVersion/dwBuildNumber }
Win32MajorVersion: Integer = 0;
Win32MinorVersion: Integer = 0;
Win32BuildNumber: Integer = 0;
{ Win32 OS extra version info string -
see TOSVersionInfo.szCSDVersion }
Win32CSDVersion: string = '';
{ Currency and date/time formatting options
The initial values of these variables are fetched from the system registry
using the GetLocaleInfo function in the Win32 API. The description of each
variable specifies the LOCALE_XXXX constant used to fetch the initial
value.
CurrencyString - Defines the currency symbol used in floating-point to
decimal conversions. The initial value is fetched from LOCALE_SCURRENCY.
CurrencyFormat - Defines the currency symbol placement and separation
used in floating-point to decimal conversions. Possible values are:
0 = '$1'
1 = '1$'
2 = '$ 1'
3 = '1 $'
The initial value is fetched from LOCALE_ICURRENCY.
NegCurrFormat - Defines the currency format for used in floating-point to
decimal conversions of negative numbers. Possible values are:
0 = '($1)' 4 = '(1$)' 8 = '-1 $' 12 = '$ -1'
1 = '-$1' 5 = '-1$' 9 = '-$ 1' 13 = '1- $'
2 = '$-1' 6 = '1-$' 10 = '1 $-' 14 = '($ 1)'
3 = '$1-' 7 = '1$-' 11 = '$ 1-' 15 = '(1 $)'
The initial value is fetched from LOCALE_INEGCURR.
ThousandSeparator - The character used to separate thousands in numbers
with more than three digits to the left of the decimal separator. The
initial value is fetched from LOCALE_STHOUSAND.
DecimalSeparator - The character used to separate the integer part from
the fractional part of a number. The initial value is fetched from
LOCALE_SDECIMAL.
CurrencyDecimals - The number of digits to the right of the decimal point
in a currency amount. The initial value is fetched from LOCALE_ICURRDIGITS.
DateSeparator - The character used to separate the year, month, and day
parts of a date value. The initial value is fetched from LOCATE_SDATE.
ShortDateFormat - The format string used to convert a date value to a
short string suitable for editing. For a complete description of date and
time format strings, refer to the documentation for the FormatDate
function. The short date format should only use the date separator
character and the m, mm, d, dd, yy, and yyyy format specifiers. The
initial value is fetched from LOCALE_SSHORTDATE.
LongDateFormat - The format string used to convert a date value to a long
string suitable for display but not for editing. For a complete description
of date and time format strings, refer to the documentation for the
FormatDate function. The initial value is fetched from LOCALE_SLONGDATE.
TimeSeparator - The character used to separate the hour, minute, and
second parts of a time value. The initial value is fetched from
LOCALE_STIME.
TimeAMString - The suffix string used for time values between 00:00 and
11:59 in 12-hour clock format. The initial value is fetched from
LOCALE_S1159.
TimePMString - The suffix string used for time values between 12:00 and
23:59 in 12-hour clock format. The initial value is fetched from
LOCALE_S2359.
ShortTimeFormat - The format string used to convert a time value to a
short string with only hours and minutes. The default value is computed
from LOCALE_ITIME and LOCALE_ITLZERO.
LongTimeFormat - The format string used to convert a time value to a long
string with hours, minutes, and seconds. The default value is computed
from LOCALE_ITIME and LOCALE_ITLZERO.
ShortMonthNames - Array of strings containing short month names. The mmm
format specifier in a format string passed to FormatDate causes a short
month name to be substituted. The default values are fecthed from the
LOCALE_SABBREVMONTHNAME system locale entries.
LongMonthNames - Array of strings containing long month names. The mmmm
format specifier in a format string passed to FormatDate causes a long
month name to be substituted. The default values are fecthed from the
LOCALE_SMONTHNAME system locale entries.
ShortDayNames - Array of strings containing short day names. The ddd
format specifier in a format string passed to FormatDate causes a short
day name to be substituted. The default values are fecthed from the
LOCALE_SABBREVDAYNAME system locale entries.
LongDayNames - Array of strings containing long day names. The dddd
format specifier in a format string passed to FormatDate causes a long
day name to be substituted. The default values are fecthed from the
LOCALE_SDAYNAME system locale entries.
ListSeparator - The character used to separate items in a list. The
initial value is fetched from LOCALE_SLIST.
TwoDigitYearCenturyWindow - Determines what century is added to two
digit years when converting string dates to numeric dates. This value
is subtracted from the current year before extracting the century.
This can be used to extend the lifetime of existing applications that
are inextricably tied to 2 digit year data entry. The best solution
to Year 2000 (Y2k) issues is not to accept 2 digit years at all - require
4 digit years in data entry to eliminate century ambiguities.
Examples:
Current TwoDigitCenturyWindow Century StrToDate() of:
Year Value Pivot '01/01/03' '01/01/68' '01/01/50'
-------------------------------------------------------------------------
1998 0 1900 1903 1968 1950
2002 0 2000 2003 2068 2050
1998 50 (default) 1948 2003 1968 1950
2002 50 (default) 1952 2003 1968 2050
2020 50 (default) 1970 2003 2068 2050
}
var
CurrencyString: string;
CurrencyFormat: Byte;
NegCurrFormat: Byte;
ThousandSeparator: Char;
DecimalSeparator: Char;
CurrencyDecimals: Byte;
DateSeparator: Char;
ShortDateFormat: string;
LongDateFormat: string;
TimeSeparator: Char;
TimeAMString: string;
TimePMString: string;
ShortTimeFormat: string;
LongTimeFormat: string;
ShortMonthNames: array[1..12] of string;
LongMonthNames: array[1..12] of string;
ShortDayNames: array[1..7] of string;
LongDayNames: array[1..7] of string;
SysLocale: TSysLocale;
EraNames: array[1..7] of string;
EraYearOffsets: array[1..7] of Integer;
TwoDigitYearCenturyWindow: Word = 50;
ListSeparator: Char;
function Languages: TLanguages;
{ Memory management routines }
{ AllocMem allocates a block of the given size on the heap. Each byte in
the allocated buffer is set to zero. To dispose the buffer, use the
FreeMem standard procedure. }
function AllocMem(Size: Cardinal): Pointer;
{ Exit procedure handling }
{ AddExitProc adds the given procedure to the run-time library's exit
procedure list. When an application terminates, its exit procedures are
executed in reverse order of definition, i.e. the last procedure passed
to AddExitProc is the first one to get executed upon termination. }
procedure AddExitProc(Proc: TProcedure);
{ String handling routines }
{ NewStr allocates a string on the heap. NewStr is provided for backwards
compatibility only. }
function NewStr(const S: string): PString;
{ DisposeStr disposes a string pointer that was previously allocated using
NewStr. DisposeStr is provided for backwards compatibility only. }
procedure DisposeStr(P: PString);
{ AssignStr assigns a new dynamically allocated string to the given string
pointer. AssignStr is provided for backwards compatibility only. }
procedure AssignStr(var P: PString; const S: string);
{ AppendStr appends S to the end of Dest. AppendStr is provided for
backwards compatibility only. Use "Dest := Dest + S" instead. }
procedure AppendStr(var Dest: string; const S: string);
{ UpperCase converts all ASCII characters in the given string to upper case.
The conversion affects only 7-bit ASCII characters between 'a' and 'z'. To
convert 8-bit international characters, use AnsiUpperCase. }
function UpperCase(const S: string): string;
{ LowerCase converts all ASCII characters in the given string to lower case.
The conversion affects only 7-bit ASCII characters between 'A' and 'Z'. To
convert 8-bit international characters, use AnsiLowerCase. }
function LowerCase(const S: string): string;
{ CompareStr compares S1 to S2, with case-sensitivity. The return value is
less than 0 if S1 < S2, 0 if S1 = S2, or greater than 0 if S1 > S2. The
compare operation is based on the 8-bit ordinal value of each character
and is not affected by the current Windows locale. }
function CompareStr(const S1, S2: string): Integer;
{ CompareMem performs a binary compare of Length bytes of memory referenced
by P1 to that of P2. CompareMem returns True if the memory referenced by
P1 is identical to that of P2. }
function CompareMem(P1, P2: Pointer; Length: Integer): Boolean; assembler;
{ CompareText compares S1 to S2, without case-sensitivity. The return value
is the same as for CompareStr. The compare operation is based on the 8-bit
ordinal value of each character, after converting 'a'..'z' to 'A'..'Z',
and is not affected by the current Windows locale. }
function CompareText(const S1, S2: string): Integer;
{ SameText compares S1 to S2, without case-sensitivity. Returns true if
S1 and S2 are the equal, that is, if CompareText would return 0. SameText
has the same 8-bit limitations as CompareText }
function SameText(const S1, S2: string): Boolean;
{ AnsiUpperCase converts all characters in the given string to upper case.
The conversion uses the current Windows locale. }
function AnsiUpperCase(const S: string): string;
{ AnsiLowerCase converts all characters in the given string to lower case.
The conversion uses the current Windows locale. }
function AnsiLowerCase(const S: string): string;
{ AnsiCompareStr compares S1 to S2, with case-sensitivity. The compare
operation is controlled by the current Windows locale. The return value
is the same as for CompareStr. }
function AnsiCompareStr(const S1, S2: string): Integer;
{ AnsiSameStr compares S1 to S2, with case-sensitivity. The compare
operation is controlled by the current Windows locale. The return value
is True if AnsiCompareStr would have returned 0. }
function AnsiSameStr(const S1, S2: string): Boolean;
{ AnsiCompareText compares S1 to S2, without case-sensitivity. The compare
operation is controlled by the current Windows locale. The return value
is the same as for CompareStr. }
function AnsiCompareText(const S1, S2: string): Integer;
{ AnsiSameText compares S1 to S2, without case-sensitivity. The compare
operation is controlled by the current Windows locale. The return value
is True if AnsiCompareText would have returned 0. }
function AnsiSameText(const S1, S2: string): Boolean;
{ AnsiStrComp compares S1 to S2, with case-sensitivity. The compare
operation is controlled by the current Windows locale. The return value
is the same as for CompareStr. }
function AnsiStrComp(S1, S2: PChar): Integer;
{ AnsiStrIComp compares S1 to S2, without case-sensitivity. The compare
operation is controlled by the current Windows locale. The return value
is the same as for CompareStr. }
function AnsiStrIComp(S1, S2: PChar): Integer;
{ AnsiStrLComp compares S1 to S2, with case-sensitivity, up to a maximum
length of MaxLen bytes. The compare operation is controlled by the
current Windows locale. The return value is the same as for CompareStr. }
function AnsiStrLComp(S1, S2: PChar; MaxLen: Cardinal): Integer;
{ AnsiStrLIComp compares S1 to S2, without case-sensitivity, up to a maximum
length of MaxLen bytes. The compare operation is controlled by the
current Windows locale. The return value is the same as for CompareStr. }
function AnsiStrLIComp(S1, S2: PChar; MaxLen: Cardinal): Integer;
{ AnsiStrLower converts all characters in the given string to lower case.
The conversion uses the current Windows locale. }
function AnsiStrLower(Str: PChar): PChar;
{ AnsiStrUpper converts all characters in the given string to upper case.
The conversion uses the current Windows locale. }
function AnsiStrUpper(Str: PChar): PChar;
{ AnsiLastChar returns a pointer to the last full character in the string.
This function supports multibyte characters }
function AnsiLastChar(const S: string): PChar;
{ AnsiStrLastChar returns a pointer to the last full character in the string.
This function supports multibyte characters. }
function AnsiStrLastChar(P: PChar): PChar;
{ Trim trims leading and trailing spaces and control characters from the
given string. }
function Trim(const S: string): string;
{ TrimLeft trims leading spaces and control characters from the given
string. }
function TrimLeft(const S: string): string;
{ TrimRight trims trailing spaces and control characters from the given
string. }
function TrimRight(const S: string): string;
{ QuotedStr returns the given string as a quoted string. A single quote
character is inserted at the beginning and the end of the string, and
for each single quote character in the string, another one is added. }
function QuotedStr(const S: string): string;
{ AnsiQuotedStr returns the given string as a quoted string, using the
provided Quote character. A Quote character is inserted at the beginning
and end of thestring, and each Quote character in the string is doubled.
This function supports multibyte character strings (MBCS). }
function AnsiQuotedStr(const S: string; Quote: Char): string;
{ AnsiExtractQuotedStr removes the Quote characters from the beginning and end
of a quoted string, and reduces pairs of Quote characters within the quoted
string to a single character. If the first character in Src is not the Quote
character, the function returns an empty string. The function copies
characters from the Src to the result string until the second solitary
Quote character or the first null character in Src. The Src parameter is
updated to point to the first character following the quoted string. If
the Src string does not contain a matching end Quote character, the Src
parameter is updated to point to the terminating null character in Src.
This function supports multibyte character strings (MBCS). }
function AnsiExtractQuotedStr(var Src: PChar; Quote: Char): string;
{ AdjustLineBreaks adjusts all line breaks in the given string to be true
CR/LF sequences. The function changes any CR characters not followed by
a LF and any LF characters not preceded by a CR into CR/LF pairs. }
function AdjustLineBreaks(const S: string): string;
{ IsValidIdent returns true if the given string is a valid identifier. An
identifier is defined as a character from the set ['A'..'Z', 'a'..'z', '_']
followed by zero or more characters from the set ['A'..'Z', 'a'..'z',
'0..'9', '_']. }
function IsValidIdent(const Ident: string): Boolean;
{ IntToStr converts the given value to its decimal string representation. }
function IntToStr(Value: Integer): string; overload;
function IntToStr(Value: Int64): string; overload;
{ IntToHex converts the given value to a hexadecimal string representation
with the minimum number of digits specified. }
function IntToHex(Value: Integer; Digits: Integer): string; overload;
function IntToHex(Value: Int64; Digits: Integer): string; overload;
{ StrToInt converts the given string to an integer value. If the string
doesn't contain a valid value, an EConvertError exception is raised. }
function StrToInt(const S: string): Integer;
function StrToInt64(const S: string): Int64;
{ StrToIntDef converts the given string to an integer value. If the string
doesn't contain a valid value, the value given by Default is returned. }
function StrToIntDef(const S: string; Default: Integer): Integer;
function StrToInt64Def(const S: string; Default: Int64): Int64;
{ LoadStr loads the string resource given by Ident from the application's
executable file. If the string resource does not exist, an empty string
is returned. }
function LoadStr(Ident: Integer): string;
{ LoadStr loads the string resource given by Ident from the application's
executable file, and uses it as the format string in a call to the
Format function with the given arguments. }
function FmtLoadStr(Ident: Integer; const Args: array of const): string;
{ File management routines }
{ FileOpen opens the specified file using the specified access mode. The
access mode value is constructed by OR-ing one of the fmOpenXXXX constants
with one of the fmShareXXXX constants. If the return value is positive,
the function was successful and the value is the file handle of the opened
file. A return value of -1 indicates that an error occurred. }
function FileOpen(const FileName: string; Mode: LongWord): Integer;
{ FileCreate creates a new file by the specified name. If the return value
is positive, the function was successful and the value is the file handle
of the new file. A return value of -1 indicates that an error occurred. }
function FileCreate(const FileName: string): Integer;
{ FileRead reads Count bytes from the file given by Handle into the buffer
specified by Buffer. The return value is the number of bytes actually
read; it is less than Count if the end of the file was reached. The return
value is -1 if an error occurred. }
function FileRead(Handle: Integer; var Buffer; Count: LongWord): Integer;
{ FileWrite writes Count bytes to the file given by Handle from the buffer
specified by Buffer. The return value is the number of bytes actually
written, or -1 if an error occurred. }
function FileWrite(Handle: Integer; const Buffer; Count: LongWord): Integer;
{ FileSeek changes the current position of the file given by Handle to be
Offset bytes relative to the point given by Origin. Origin = 0 means that
Offset is relative to the beginning of the file, Origin = 1 means that
Offset is relative to the current position, and Origin = 2 means that
Offset is relative to the end of the file. The return value is the new
current position, relative to the beginning of the file, or -1 if an error
occurred. }
function FileSeek(Handle, Offset, Origin: Integer): Integer; overload;
function FileSeek(Handle: Integer; const Offset: Int64; Origin: Integer): Int64; overload;
{ FileClose closes the specified file. }
procedure FileClose(Handle: Integer);
{ FileAge returns the date-and-time stamp of the specified file. The return
value can be converted to a TDateTime value using the FileDateToDateTime
function. The return value is -1 if the file does not exist. }
function FileAge(const FileName: string): Integer;
{ FileExists returns a boolean value that indicates whether the specified
file exists. }
function FileExists(const FileName: string): Boolean;
{ FindFirst searches the directory given by Path for the first entry that
matches the filename given by Path and the attributes given by Attr. The
result is returned in the search record given by SearchRec. The return
value is zero if the function was successful. Otherwise the return value
is a Windows error code. FindFirst is typically used in conjunction with
FindNext and FindClose as follows:
Result := FindFirst(Path, Attr, SearchRec);
while Result = 0 do
begin
ProcessSearchRec(SearchRec);
Result := FindNext(SearchRec);
end;
FindClose(SearchRec);
where ProcessSearchRec represents user-defined code that processes the
information in a search record. }
function FindFirst(const Path: string; Attr: Integer;
var F: TSearchRec): Integer;
{ FindNext returs the next entry that matches the name and attributes
specified in a previous call to FindFirst. The search record must be one
that was passed to FindFirst. The return value is zero if the function was
successful. Otherwise the return value is a Windows error code. }
function FindNext(var F: TSearchRec): Integer;
{ FindClose terminates a FindFirst/FindNext sequence. FindClose does nothing
in the 16-bit version of Windows, but is required in the 32-bit version,
so for maximum portability every FindFirst/FindNext sequence should end
with a call to FindClose. }
procedure FindClose(var F: TSearchRec);
{ FileGetDate returns the DOS date-and-time stamp of the file given by
Handle. The return value is -1 if the handle is invalid. The
FileDateToDateTime function can be used to convert the returned value to
a TDateTime value. }
function FileGetDate(Handle: Integer): Integer;
{ FileSetDate sets the DOS date-and-time stamp of the file given by Handle
to the value given by Age. The DateTimeToFileDate function can be used to
convert a TDateTime value to a DOS date-and-time stamp. The return value
is zero if the function was successful. Otherwise the return value is a
Windows error code. }
function FileSetDate(Handle: Integer; Age: Integer): Integer;
{ FileGetAttr returns the file attributes of the file given by FileName. The
attributes can be examined by AND-ing with the faXXXX constants defined
above. A return value of -1 indicates that an error occurred. }
function FileGetAttr(const FileName: string): Integer;
{ FileSetAttr sets the file attributes of the file given by FileName to the
value given by Attr. The attribute value is formed by OR-ing the
appropriate faXXXX constants. The return value is zero if the function was
successful. Otherwise the return value is a Windows error code. }
function FileSetAttr(const FileName: string; Attr: Integer): Integer;
{ DeleteFile deletes the file given by FileName. The return value is True if
the file was successfully deleted, or False if an error occurred. }
function DeleteFile(const FileName: string): Boolean;
{ RenameFile renames the file given by OldName to the name given by NewName.
The return value is True if the file was successfully renamed, or False if
an error occurred. }
function RenameFile(const OldName, NewName: string): Boolean;
{ ChangeFileExt changes the extension of a filename. FileName specifies a
filename with or without an extension, and Extension specifies the new
extension for the filename. The new extension can be a an empty string or
a period followed by up to three characters. }
function ChangeFileExt(const FileName, Extension: string): string;
{ ExtractFilePath extracts the drive and directory parts of the given
filename. The resulting string is the leftmost characters of FileName,
up to and including the colon or backslash that separates the path
information from the name and extension. The resulting string is empty
if FileName contains no drive and directory parts. }
function ExtractFilePath(const FileName: string): string;
{ ExtractFileDir extracts the drive and directory parts of the given
filename. The resulting string is a directory name suitable for passing
to SetCurrentDir, CreateDir, etc. The resulting string is empty if
FileName contains no drive and directory parts. }
function ExtractFileDir(const FileName: string): string;
{ ExtractFileDrive extracts the drive part of the given filename. For
filenames with drive letters, the resulting string is '<drive>:'.
For filenames with a UNC path, the resulting string is in the form
'\\<servername>\<sharename>'. If the given path contains neither
style of filename, the result is an empty string. }
function ExtractFileDrive(const FileName: string): string;
{ ExtractFileName extracts the name and extension parts of the given
filename. The resulting string is the leftmost characters of FileName,
starting with the first character after the colon or backslash that
separates the path information from the name and extension. The resulting
string is equal to FileName if FileName contains no drive and directory
parts. }
function ExtractFileName(const FileName: string): string;
{ ExtractFileExt extracts the extension part of the given filename. The
resulting string includes the period character that separates the name
and extension parts. The resulting string is empty if the given filename
has no extension. }
function ExtractFileExt(const FileName: string): string;
{ ExpandFileName expands the given filename to a fully qualified filename.
The resulting string consists of a drive letter, a colon, a root relative
directory path, and a filename. Embedded '.' and '..' directory references
are removed. }
function ExpandFileName(const FileName: string): string;
{ ExpandUNCFileName expands the given filename to a fully qualified filename.
This function is the same as ExpandFileName except that it will return the
drive portion of the filename in the format '\\<servername>\<sharename> if
that drive is actually a network resource instead of a local resource.
Like ExpandFileName, embedded '.' and '..' directory references are
removed. }
function ExpandUNCFileName(const FileName: string): string;
{ ExtractRelativePath will return a file path name relative to the given
BaseName. It strips the common path dirs and adds '..\' for each level
up from the BaseName path. }
function ExtractRelativePath(const BaseName, DestName: string): string;
{ ExtractShortPathName will convert the given filename to the short form
by calling the GetShortPathName API. Will return an empty string if
the file or directory specified does not exist }
function ExtractShortPathName(const FileName: string): string;
{ FileSearch searches for the file given by Name in the list of directories
given by DirList. The directory paths in DirList must be separated by
semicolons. The search always starts with the current directory of the
current drive. The returned value is a concatenation of one of the
directory paths and the filename, or an empty string if the file could not
be located. }
function FileSearch(const Name, DirList: string): string;
{ DiskFree returns the number of free bytes on the specified drive number,
where 0 = Current, 1 = A, 2 = B, etc. DiskFree returns -1 if the drive
number is invalid. }
function DiskFree(Drive: Byte): Int64;
{ DiskSize returns the size in bytes of the specified drive number, where
0 = Current, 1 = A, 2 = B, etc. DiskSize returns -1 if the drive number
is invalid. }
function DiskSize(Drive: Byte): Int64;
{ FileDateToDateTime converts a DOS date-and-time value to a TDateTime
value. The FileAge, FileGetDate, and FileSetDate routines operate on DOS
date-and-time values, and the Time field of a TSearchRec used by the
FindFirst and FindNext functions contains a DOS date-and-time value. }
function FileDateToDateTime(FileDate: Integer): TDateTime;
{ DateTimeToFileDate converts a TDateTime value to a DOS date-and-time
value. The FileAge, FileGetDate, and FileSetDate routines operate on DOS
date-and-time values, and the Time field of a TSearchRec used by the
FindFirst and FindNext functions contains a DOS date-and-time value. }
function DateTimeToFileDate(DateTime: TDateTime): Integer;
{ GetCurrentDir returns the current directory. }
function GetCurrentDir: string;
{ SetCurrentDir sets the current directory. The return value is True if
the current directory was successfully changed, or False if an error
occurred. }
function SetCurrentDir(const Dir: string): Boolean;
{ CreateDir creates a new directory. The return value is True if a new
directory was successfully created, or False if an error occurred. }
function CreateDir(const Dir: string): Boolean;
{ RemoveDir deletes an existing empty directory. The return value is
True if the directory was successfully deleted, or False if an error
occurred. }
function RemoveDir(const Dir: string): Boolean;
{ PChar routines }
{ const params help simplify C++ code. No effect on pascal code }
{ StrLen returns the number of characters in Str, not counting the null
terminator. }
function StrLen(const Str: PChar): Cardinal;
{ StrEnd returns a pointer to the null character that terminates Str. }
function StrEnd(const Str: PChar): PChar;
{ StrMove copies exactly Count characters from Source to Dest and returns
Dest. Source and Dest may overlap. }
function StrMove(Dest: PChar; const Source: PChar; Count: Cardinal): PChar;
{ StrCopy copies Source to Dest and returns Dest. }
function StrCopy(Dest: PChar; const Source: PChar): PChar;
{ StrECopy copies Source to Dest and returns StrEnd(Dest). }
function StrECopy(Dest:PChar; const Source: PChar): PChar;
{ StrLCopy copies at most MaxLen characters from Source to Dest and
returns Dest. }
function StrLCopy(Dest: PChar; const Source: PChar; MaxLen: Cardinal): PChar;
{ StrPCopy copies the Pascal style string Source into Dest and
returns Dest. }
function StrPCopy(Dest: PChar; const Source: string): PChar;
{ StrPLCopy copies at most MaxLen characters from the Pascal style string
Source into Dest and returns Dest. }
function StrPLCopy(Dest: PChar; const Source: string;
MaxLen: Cardinal): PChar;
{ StrCat appends a copy of Source to the end of Dest and returns Dest. }
function StrCat(Dest: PChar; const Source: PChar): PChar;
{ StrLCat appends at most MaxLen - StrLen(Dest) characters from Source to
the end of Dest, and returns Dest. }
function StrLCat(Dest: PChar; const Source: PChar; MaxLen: Cardinal): PChar;
{ StrComp compares Str1 to Str2. The return value is less than 0 if
Str1 < Str2, 0 if Str1 = Str2, or greater than 0 if Str1 > Str2. }
function StrComp(const Str1, Str2: PChar): Integer;
{ StrIComp compares Str1 to Str2, without case sensitivity. The return
value is the same as StrComp. }
function StrIComp(const Str1, Str2: PChar): Integer;
{ StrLComp compares Str1 to Str2, for a maximum length of MaxLen
characters. The return value is the same as StrComp. }
function StrLComp(const Str1, Str2: PChar; MaxLen: Cardinal): Integer;
{ StrLIComp compares Str1 to Str2, for a maximum length of MaxLen
characters, without case sensitivity. The return value is the same
as StrComp. }
function StrLIComp(const Str1, Str2: PChar; MaxLen: Cardinal): Integer;
{ StrScan returns a pointer to the first occurrence of Chr in Str. If Chr
does not occur in Str, StrScan returns NIL. The null terminator is
considered to be part of the string. }
function StrScan(const Str: PChar; Chr: Char): PChar;
{ StrRScan returns a pointer to the last occurrence of Chr in Str. If Chr
does not occur in Str, StrRScan returns NIL. The null terminator is
considered to be part of the string. }
function StrRScan(const Str: PChar; Chr: Char): PChar;
{ StrPos returns a pointer to the first occurrence of Str2 in Str1. If
Str2 does not occur in Str1, StrPos returns NIL. }
function StrPos(const Str1, Str2: PChar): PChar;
{ StrUpper converts Str to upper case and returns Str. }
function StrUpper(Str: PChar): PChar;
{ StrLower converts Str to lower case and returns Str. }
function StrLower(Str: PChar): PChar;
{ StrPas converts Str to a Pascal style string. This function is provided
for backwards compatibility only. To convert a null terminated string to
a Pascal style string, use a string type cast or an assignment. }
function StrPas(const Str: PChar): string;
{ StrAlloc allocates a buffer of the given size on the heap. The size of
the allocated buffer is encoded in a four byte header that immediately
preceeds the buffer. To dispose the buffer, use StrDispose. }
function StrAlloc(Size: Cardinal): PChar;
{ StrBufSize returns the allocated size of the given buffer, not including
the two byte header. }
function StrBufSize(const Str: PChar): Cardinal;
{ StrNew allocates a copy of Str on the heap. If Str is NIL, StrNew returns
NIL and doesn't allocate any heap space. Otherwise, StrNew makes a
duplicate of Str, obtaining space with a call to the StrAlloc function,
and returns a pointer to the duplicated string. To dispose the string,
use StrDispose. }
function StrNew(const Str: PChar): PChar;
{ StrDispose disposes a string that was previously allocated with StrAlloc
or StrNew. If Str is NIL, StrDispose does nothing. }
procedure StrDispose(Str: PChar);
{ String formatting routines }
{ The Format routine formats the argument list given by the Args parameter
using the format string given by the Format parameter.
Format strings contain two types of objects--plain characters and format
specifiers. Plain characters are copied verbatim to the resulting string.
Format specifiers fetch arguments from the argument list and apply
formatting to them.
Format specifiers have the following form:
"%" [index ":"] ["-"] [width] ["." prec] type
A format specifier begins with a % character. After the % come the
following, in this order:
- an optional argument index specifier, [index ":"]
- an optional left-justification indicator, ["-"]
- an optional width specifier, [width]
- an optional precision specifier, ["." prec]
- the conversion type character, type
The following conversion characters are supported:
d Decimal. The argument must be an integer value. The value is converted
to a string of decimal digits. If the format string contains a precision
specifier, it indicates that the resulting string must contain at least
the specified number of digits; if the value has less digits, the
resulting string is left-padded with zeros.
u Unsigned decimal. Similar to 'd' but no sign is output.
e Scientific. The argument must be a floating-point value. The value is
converted to a string of the form "-d.ddd...E+ddd". The resulting
string starts with a minus sign if the number is negative, and one digit
always precedes the decimal point. The total number of digits in the
resulting string (including the one before the decimal point) is given
by the precision specifer in the format string--a default precision of
15 is assumed if no precision specifer is present. The "E" exponent
character in the resulting string is always followed by a plus or minus
sign and at least three digits.
f Fixed. The argument must be a floating-point value. The value is
converted to a string of the form "-ddd.ddd...". The resulting string
starts with a minus sign if the number is negative. The number of digits
after the decimal point is given by the precision specifier in the
format string--a default of 2 decimal digits is assumed if no precision
specifier is present.
g General. The argument must be a floating-point value. The value is
converted to the shortest possible decimal string using fixed or
scientific format. The number of significant digits in the resulting
string is given by the precision specifier in the format string--a
default precision of 15 is assumed if no precision specifier is present.
Trailing zeros are removed from the resulting string, and a decimal
point appears only if necessary. The resulting string uses fixed point
format if the number of digits to the left of the decimal point in the
value is less than or equal to the specified precision, and if the
value is greater than or equal to 0.00001. Otherwise the resulting
string uses scientific format.
n Number. The argument must be a floating-point value. The value is
converted to a string of the form "-d,ddd,ddd.ddd...". The "n" format
corresponds to the "f" format, except that the resulting string
contains thousand separators.
m Money. The argument must be a floating-point value. The value is
converted to a string that represents a currency amount. The conversion
is controlled by the CurrencyString, CurrencyFormat, NegCurrFormat,
ThousandSeparator, DecimalSeparator, and CurrencyDecimals global
variables, all of which are initialized from the Currency Format in
the International section of the Windows Control Panel. If the format
string contains a precision specifier, it overrides the value given
by the CurrencyDecimals global variable.
p Pointer. The argument must be a pointer value. The value is converted
to a string of the form "XXXX:YYYY" where XXXX and YYYY are the
segment and offset parts of the pointer expressed as four hexadecimal
digits.
s String. The argument must be a character, a string, or a PChar value.
The string or character is inserted in place of the format specifier.
The precision specifier, if present in the format string, specifies the
maximum length of the resulting string. If the argument is a string
that is longer than this maximum, the string is truncated.
x Hexadecimal. The argument must be an integer value. The value is
converted to a string of hexadecimal digits. If the format string
contains a precision specifier, it indicates that the resulting string
must contain at least the specified number of digits; if the value has
less digits, the resulting string is left-padded with zeros.
Conversion characters may be specified in upper case as well as in lower
case--both produce the same results.
For all floating-point formats, the actual characters used as decimal and
thousand separators are obtained from the DecimalSeparator and
ThousandSeparator global variables.
Index, width, and precision specifiers can be specified directly using
decimal digit string (for example "%10d"), or indirectly using an asterisk
charcater (for example "%*.*f"). When using an asterisk, the next argument
in the argument list (which must be an integer value) becomes the value
that is actually used. For example "Format('%*.*f', [8, 2, 123.456])" is
the same as "Format('%8.2f', [123.456])".
A width specifier sets the minimum field width for a conversion. If the
resulting string is shorter than the minimum field width, it is padded
with blanks to increase the field width. The default is to right-justify
the result by adding blanks in front of the value, but if the format
specifier contains a left-justification indicator (a "-" character
preceding the width specifier), the result is left-justified by adding
blanks after the value.
An index specifier sets the current argument list index to the specified
value. The index of the first argument in the argument list is 0. Using
index specifiers, it is possible to format the same argument multiple
times. For example "Format('%d %d %0:d %d', [10, 20])" produces the string
'10 20 10 20'.
The Format function can be combined with other formatting functions. For
example
S := Format('Your total was %s on %s', [
FormatFloat('$#,##0.00;;zero', Total),
FormatDateTime('mm/dd/yy', Date)]);
which uses the FormatFloat and FormatDateTime functions to customize the
format beyond what is possible with Format. }
function Format(const Format: string; const Args: array of const): string;
{ FmtStr formats the argument list given by Args using the format string
given by Format into the string variable given by Result. For further
details, see the description of the Format function. }
procedure FmtStr(var Result: string; const Format: string;
const Args: array of const);
{ StrFmt formats the argument list given by Args using the format string
given by Format into the buffer given by Buffer. It is up to the caller to
ensure that Buffer is large enough for the resulting string. The returned
value is Buffer. For further details, see the description of the Format
function. }
function StrFmt(Buffer, Format: PChar; const Args: array of const): PChar;
{ StrFmt formats the argument list given by Args using the format string
given by Format into the buffer given by Buffer. The resulting string will
contain no more than MaxLen characters, not including the null terminator.
The returned value is Buffer. For further details, see the description of
the Format function. }
function StrLFmt(Buffer: PChar; MaxLen: Cardinal; Format: PChar;
const Args: array of const): PChar;
{ FormatBuf formats the argument list given by Args using the format string
given by Format and FmtLen into the buffer given by Buffer and BufLen.
The Format parameter is a reference to a buffer containing FmtLen
characters, and the Buffer parameter is a reference to a buffer of BufLen
characters. The returned value is the number of characters actually stored
in Buffer. The returned value is always less than or equal to BufLen. For
further details, see the description of the Format function. }
function FormatBuf(var Buffer; BufLen: Cardinal; const Format;
FmtLen: Cardinal; const Args: array of const): Cardinal;
{ Floating point conversion routines }
{ FloatToStr converts the floating-point value given by Value to its string
representation. The conversion uses general number format with 15
significant digits. For further details, see the description of the
FloatToStrF function. }
function FloatToStr(Value: Extended): string;
{ CurrToStr converts the currency value given by Value to its string
representation. The conversion uses general number format. For further
details, see the description of the CurrToStrF function. }
function CurrToStr(Value: Currency): string;
{ FloatToStrF converts the floating-point value given by Value to its string
representation. The Format parameter controls the format of the resulting
string. The Precision parameter specifies the precision of the given value.
It should be 7 or less for values of type Single, 15 or less for values of
type Double, and 18 or less for values of type Extended. The meaning of the
Digits parameter depends on the particular format selected.
The possible values of the Format parameter, and the meaning of each, are
described below.
ffGeneral - General number format. The value is converted to the shortest
possible decimal string using fixed or scientific format. Trailing zeros
are removed from the resulting string, and a decimal point appears only
if necessary. The resulting string uses fixed point format if the number
of digits to the left of the decimal point in the value is less than or
equal to the specified precision, and if the value is greater than or
equal to 0.00001. Otherwise the resulting string uses scientific format,
and the Digits parameter specifies the minimum number of digits in the
exponent (between 0 and 4).
ffExponent - Scientific format. The value is converted to a string of the
form "-d.ddd...E+dddd". The resulting string starts with a minus sign if
the number is negative, and one digit always precedes the decimal point.
The total number of digits in the resulting string (including the one
before the decimal point) is given by the Precision parameter. The "E"
exponent character in the resulting string is always followed by a plus
or minus sign and up to four digits. The Digits parameter specifies the
minimum number of digits in the exponent (between 0 and 4).
ffFixed - Fixed point format. The value is converted to a string of the
form "-ddd.ddd...". The resulting string starts with a minus sign if the
number is negative, and at least one digit always precedes the decimal
point. The number of digits after the decimal point is given by the Digits
parameter--it must be between 0 and 18. If the number of digits to the
left of the decimal point is greater than the specified precision, the
resulting value will use scientific format.
ffNumber - Number format. The value is converted to a string of the form
"-d,ddd,ddd.ddd...". The ffNumber format corresponds to the ffFixed format,
except that the resulting string contains thousand separators.
ffCurrency - Currency format. The value is converted to a string that
represents a currency amount. The conversion is controlled by the
CurrencyString, CurrencyFormat, NegCurrFormat, ThousandSeparator, and
DecimalSeparator global variables, all of which are initialized from the
Currency Format in the International section of the Windows Control Panel.
The number of digits after the decimal point is given by the Digits
parameter--it must be between 0 and 18.
For all formats, the actual characters used as decimal and thousand
separators are obtained from the DecimalSeparator and ThousandSeparator
global variables.
If the given value is a NAN (not-a-number), the resulting string is 'NAN'.
If the given value is positive infinity, the resulting string is 'INF'. If
the given value is negative infinity, the resulting string is '-INF'. }
function FloatToStrF(Value: Extended; Format: TFloatFormat;
Precision, Digits: Integer): string;
{ CurrToStrF converts the currency value given by Value to its string
representation. A call to CurrToStrF corresponds to a call to
FloatToStrF with an implied precision of 19 digits. }
function CurrToStrF(Value: Currency; Format: TFloatFormat;
Digits: Integer): string;
{ FloatToText converts the given floating-point value to its decimal
representation using the specified format, precision, and digits. The
Value parameter must be a variable of type Extended or Currency, as
indicated by the ValueType parameter. The resulting string of characters
is stored in the given buffer, and the returned value is the number of
characters stored. The resulting string is not null-terminated. For
further details, see the description of the FloatToStrF function. }
function FloatToText(Buffer: PChar; const Value; ValueType: TFloatValue;
Format: TFloatFormat; Precision, Digits: Integer): Integer;
{ FormatFloat formats the floating-point value given by Value using the
format string given by Format. The following format specifiers are
supported in the format string:
0 Digit placeholder. If the value being formatted has a digit in the
position where the '0' appears in the format string, then that digit
is copied to the output string. Otherwise, a '0' is stored in that
position in the output string.
# Digit placeholder. If the value being formatted has a digit in the
position where the '#' appears in the format string, then that digit
is copied to the output string. Otherwise, nothing is stored in that
position in the output string.
. Decimal point. The first '.' character in the format string
determines the location of the decimal separator in the formatted
value; any additional '.' characters are ignored. The actual
character used as a the decimal separator in the output string is
determined by the DecimalSeparator global variable. The default value
of DecimalSeparator is specified in the Number Format of the
International section in the Windows Control Panel.
, Thousand separator. If the format string contains one or more ','
characters, the output will have thousand separators inserted between
each group of three digits to the left of the decimal point. The
placement and number of ',' characters in the format string does not
affect the output, except to indicate that thousand separators are
wanted. The actual character used as a the thousand separator in the
output is determined by the ThousandSeparator global variable. The
default value of ThousandSeparator is specified in the Number Format
of the International section in the Windows Control Panel.
E+ Scientific notation. If any of the strings 'E+', 'E-', 'e+', or 'e-'
E- are contained in the format string, the number is formatted using
e+ scientific notation. A group of up to four '0' characters can
e- immediately follow the 'E+', 'E-', 'e+', or 'e-' to determine the
minimum number of digits in the exponent. The 'E+' and 'e+' formats
cause a plus sign to be output for positive exponents and a minus
sign to be output for negative exponents. The 'E-' and 'e-' formats
output a sign character only for negative exponents.
'xx' Characters enclosed in single or double quotes are output as-is, and
"xx" do not affect formatting.
; Separates sections for positive, negative, and zero numbers in the
format string.
The locations of the leftmost '0' before the decimal point in the format
string and the rightmost '0' after the decimal point in the format string
determine the range of digits that are always present in the output string.
The number being formatted is always rounded to as many decimal places as
there are digit placeholders ('0' or '#') to the right of the decimal
point. If the format string contains no decimal point, the value being
formatted is rounded to the nearest whole number.
If the number being formatted has more digits to the left of the decimal
separator than there are digit placeholders to the left of the '.'
character in the format string, the extra digits are output before the
first digit placeholder.
To allow different formats for positive, negative, and zero values, the
format string can contain between one and three sections separated by
semicolons.
One section - The format string applies to all values.
Two sections - The first section applies to positive values and zeros, and
the second section applies to negative values.
Three sections - The first section applies to positive values, the second
applies to negative values, and the third applies to zeros.
If the section for negative values or the section for zero values is empty,
that is if there is nothing between the semicolons that delimit the
section, the section for positive values is used instead.
If the section for positive values is empty, or if the entire format string
is empty, the value is formatted using general floating-point formatting
with 15 significant digits, corresponding to a call to FloatToStrF with
the ffGeneral format. General floating-point formatting is also used if
the value has more than 18 digits to the left of the decimal point and
the format string does not specify scientific notation.
The table below shows some sample formats and the results produced when
the formats are applied to different values:
Format string 1234 -1234 0.5 0
-----------------------------------------------------------------------
1234 -1234 0.5 0
0 1234 -1234 1 0
0.00 1234.00 -1234.00 0.50 0.00
#.## 1234 -1234 .5
#,##0.00 1,234.00 -1,234.00 0.50 0.00
#,##0.00;(#,##0.00) 1,234.00 (1,234.00) 0.50 0.00
#,##0.00;;Zero 1,234.00 -1,234.00 0.50 Zero
0.000E+00 1.234E+03 -1.234E+03 5.000E-01 0.000E+00
#.###E-0 1.234E3 -1.234E3 5E-1 0E0
----------------------------------------------------------------------- }
function FormatFloat(const Format: string; Value: Extended): string;
{ FormatCurr formats the currency value given by Value using the format
string given by Format. For further details, see the description of the
FormatFloat function. }
function FormatCurr(const Format: string; Value: Currency): string;
{ FloatToTextFmt converts the given floating-point value to its decimal
representation using the specified format. The Value parameter must be a
variable of type Extended or Currency, as indicated by the ValueType
parameter. The resulting string of characters is stored in the given
buffer, and the returned value is the number of characters stored. The
resulting string is not null-terminated. For further details, see the
description of the FormatFloat function. }
function FloatToTextFmt(Buffer: PChar; const Value; ValueType: TFloatValue;
Format: PChar): Integer;
{ StrToFloat converts the given string to a floating-point value. The string
must consist of an optional sign (+ or -), a string of digits with an
optional decimal point, and an optional 'E' or 'e' followed by a signed
integer. Leading and trailing blanks in the string are ignored. The
DecimalSeparator global variable defines the character that must be used
as a decimal point. Thousand separators and currency symbols are not
allowed in the string. If the string doesn't contain a valid value, an
EConvertError exception is raised. }
function StrToFloat(const S: string): Extended;
{ StrToCurr converts the given string to a currency value. For further
details, see the description of the StrToFloat function. }
function StrToCurr(const S: string): Currency;
{ TextToFloat converts the null-terminated string given by Buffer to a
floating-point value which is returned in the variable given by Value.
The Value parameter must be a variable of type Extended or Currency, as
indicated by the ValueType parameter. The return value is True if the
conversion was successful, or False if the string is not a valid
floating-point value. For further details, see the description of the
StrToFloat function. }
function TextToFloat(Buffer: PChar; var Value;
ValueType: TFloatValue): Boolean;
{ FloatToDecimal converts a floating-point value to a decimal representation
that is suited for further formatting. The Value parameter must be a
variable of type Extended or Currency, as indicated by the ValueType
parameter. For values of type Extended, the Precision parameter specifies
the requested number of significant digits in the result--the allowed range
is 1..18. For values of type Currency, the Precision parameter is ignored,
and the implied precision of the conversion is 19 digits. The Decimals
parameter specifies the requested maximum number of digits to the left of
the decimal point in the result. Precision and Decimals together control
how the result is rounded. To produce a result that always has a given
number of significant digits regardless of the magnitude of the number,
specify 9999 for the Decimals parameter. The result of the conversion is
stored in the specified TFloatRec record as follows:
Exponent - Contains the magnitude of the number, i.e. the number of
significant digits to the right of the decimal point. The Exponent field
is negative if the absolute value of the number is less than one. If the
number is a NAN (not-a-number), Exponent is set to -32768. If the number
is INF or -INF (positive or negative infinity), Exponent is set to 32767.
Negative - True if the number is negative, False if the number is zero
or positive.
Digits - Contains up to 18 (for type Extended) or 19 (for type Currency)
significant digits followed by a null terminator. The implied decimal
point (if any) is not stored in Digits. Trailing zeros are removed, and
if the resulting number is zero, NAN, or INF, Digits contains nothing but
the null terminator. }
procedure FloatToDecimal(var Result: TFloatRec; const Value;
ValueType: TFloatValue; Precision, Decimals: Integer);
{ Date/time support routines }
function DateTimeToTimeStamp(DateTime: TDateTime): TTimeStamp;
function TimeStampToDateTime(const TimeStamp: TTimeStamp): TDateTime;
function MSecsToTimeStamp(MSecs: Comp): TTimeStamp;
function TimeStampToMSecs(const TimeStamp: TTimeStamp): Comp;
{ EncodeDate encodes the given year, month, and day into a TDateTime value.
The year must be between 1 and 9999, the month must be between 1 and 12,
and the day must be between 1 and N, where N is the number of days in the
specified month. If the specified values are not within range, an
EConvertError exception is raised. The resulting value is the number of
days between 12/30/1899 and the given date. }
function EncodeDate(Year, Month, Day: Word): TDateTime;
{ EncodeTime encodes the given hour, minute, second, and millisecond into a
TDateTime value. The hour must be between 0 and 23, the minute must be
between 0 and 59, the second must be between 0 and 59, and the millisecond
must be between 0 and 999. If the specified values are not within range, an
EConvertError exception is raised. The resulting value is a number between
0 (inclusive) and 1 (not inclusive) that indicates the fractional part of
a day given by the specified time. The value 0 corresponds to midnight,
0.5 corresponds to noon, 0.75 corresponds to 6:00 pm, etc. }
function EncodeTime(Hour, Min, Sec, MSec: Word): TDateTime;
{ DecodeDate decodes the integral (date) part of the given TDateTime value
into its corresponding year, month, and day. If the given TDateTime value
is less than or equal to zero, the year, month, and day return parameters
are all set to zero. }
procedure DecodeDate(Date: TDateTime; var Year, Month, Day: Word);
{ DecodeTime decodes the fractional (time) part of the given TDateTime value
into its corresponding hour, minute, second, and millisecond. }
procedure DecodeTime(Time: TDateTime; var Hour, Min, Sec, MSec: Word);
{ DateTimeToSystemTime converts a date and time from Delphi's TDateTime
format into the Win32 API's TSystemTime format. }
procedure DateTimeToSystemTime(DateTime: TDateTime; var SystemTime: TSystemTime);
{ SystemTimeToDateTime converts a date and time from the Win32 API's
TSystemTime format into Delphi's TDateTime format. }
function SystemTimeToDateTime(const SystemTime: TSystemTime): TDateTime;
{ DayOfWeek returns the day of the week of the given date. The result is an
integer between 1 and 7, corresponding to Sunday through Saturday. }
function DayOfWeek(Date: TDateTime): Integer;
{ Date returns the current date. }
function Date: TDateTime;
{ Time returns the current time. }
function Time: TDateTime;
{ Now returns the current date and time, corresponding to Date + Time. }
function Now: TDateTime;
{ IncMonth returns Date shifted by the specified number of months.
NumberOfMonths parameter can be negative, to return a date N months ago.
If the input day of month is greater than the last day of the resulting
month, the day is set to the last day of the resulting month.
Input time of day is copied to the DateTime result. }
function IncMonth(const Date: TDateTime; NumberOfMonths: Integer): TDateTime;
{ ReplaceTime replaces the time portion of the DateTime parameter with the given
time value, adjusting the signs as needed if the date is prior to 1900
(Date value less than zero) }
procedure ReplaceTime(var DateTime: TDateTime; const NewTime: TDateTime);
{ ReplaceDate replaces the date portion of the DateTime parameter with the given
date value, adjusting as needed for negative dates }
procedure ReplaceDate(var DateTime: TDateTime; const NewDate: TDateTime);
{ IsLeapYear determines whether the given year is a leap year. }
function IsLeapYear(Year: Word): Boolean;
type
PDayTable = ^TDayTable;
TDayTable = array[1..12] of Word;
{ The MonthDays array can be used to quickly find the number of
days in a month: MonthDays[IsLeapYear(Y), M] }
const
MonthDays: array [Boolean] of TDayTable =
((31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31),
(31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31));
{ DateToStr converts the date part of the given TDateTime value to a string.
The conversion uses the format specified by the ShortDateFormat global
variable. }
function DateToStr(Date: TDateTime): string;
{ TimeToStr converts the time part of the given TDateTime value to a string.
The conversion uses the format specified by the LongTimeFormat global
variable. }
function TimeToStr(Time: TDateTime): string;
{ DateTimeToStr converts the given date and time to a string. The resulting
string consists of a date and time formatted using the ShortDateFormat and
LongTimeFormat global variables. Time information is included in the
resulting string only if the fractional part of the given date and time
value is non-zero. }
function DateTimeToStr(DateTime: TDateTime): string;
{ StrToDate converts the given string to a date value. The string must
consist of two or three numbers, separated by the character defined by
the DateSeparator global variable. The order for month, day, and year is
determined by the ShortDateFormat global variable--possible combinations
are m/d/y, d/m/y, and y/m/d. If the string contains only two numbers, it
is interpreted as a date (m/d or d/m) in the current year. Year values
between 0 and 99 are assumed to be in the current century. If the given
string does not contain a valid date, an EConvertError exception is
raised. }
function StrToDate(const S: string): TDateTime;
{ StrToTime converts the given string to a time value. The string must
consist of two or three numbers, separated by the character defined by
the TimeSeparator global variable, optionally followed by an AM or PM
indicator. The numbers represent hour, minute, and (optionally) second,
in that order. If the time is followed by AM or PM, it is assumed to be
in 12-hour clock format. If no AM or PM indicator is included, the time
is assumed to be in 24-hour clock format. If the given string does not
contain a valid time, an EConvertError exception is raised. }
function StrToTime(const S: string): TDateTime;
{ StrToDateTime converts the given string to a date and time value. The
string must contain a date optionally followed by a time. The date and
time parts of the string must follow the formats described for the
StrToDate and StrToTime functions. }
function StrToDateTime(const S: string): TDateTime;
{ FormatDateTime formats the date-and-time value given by DateTime using the
format given by Format. The following format specifiers are supported:
c Displays the date using the format given by the ShortDateFormat
global variable, followed by the time using the format given by
the LongTimeFormat global variable. The time is not displayed if
the fractional part of the DateTime value is zero.
d Displays the day as a number without a leading zero (1-31).
dd Displays the day as a number with a leading zero (01-31).
ddd Displays the day as an abbreviation (Sun-Sat) using the strings
given by the ShortDayNames global variable.
dddd Displays the day as a full name (Sunday-Saturday) using the strings
given by the LongDayNames global variable.
ddddd Displays the date using the format given by the ShortDateFormat
global variable.
dddddd Displays the date using the format given by the LongDateFormat
global variable.
g Displays the period/era as an abbreviation (Japanese and
Taiwanese locales only).
gg Displays the period/era as a full name.
e Displays the year in the current period/era as a number without
a leading zero (Japanese, Korean and Taiwanese locales only).
ee Displays the year in the current period/era as a number with
a leading zero (Japanese, Korean and Taiwanese locales only).
m Displays the month as a number without a leading zero (1-12). If
the m specifier immediately follows an h or hh specifier, the
minute rather than the month is displayed.
mm Displays the month as a number with a leading zero (01-12). If
the mm specifier immediately follows an h or hh specifier, the
minute rather than the month is displayed.
mmm Displays the month as an abbreviation (Jan-Dec) using the strings
given by the ShortMonthNames global variable.
mmmm Displays the month as a full name (January-December) using the
strings given by the LongMonthNames global variable.
yy Displays the year as a two-digit number (00-99).
yyyy Displays the year as a four-digit number (0000-9999).
h Displays the hour without a leading zero (0-23).
hh Displays the hour with a leading zero (00-23).
n Displays the minute without a leading zero (0-59).
nn Displays the minute with a leading zero (00-59).
s Displays the second without a leading zero (0-59).
ss Displays the second with a leading zero (00-59).
z Displays the millisecond without a leading zero (0-999).
zzz Displays the millisecond with a leading zero (000-999).
t Displays the time using the format given by the ShortTimeFormat
global variable.
tt Displays the time using the format given by the LongTimeFormat
global variable.
am/pm Uses the 12-hour clock for the preceding h or hh specifier, and
displays 'am' for any hour before noon, and 'pm' for any hour
after noon. The am/pm specifier can use lower, upper, or mixed
case, and the result is displayed accordingly.
a/p Uses the 12-hour clock for the preceding h or hh specifier, and
displays 'a' for any hour before noon, and 'p' for any hour after
noon. The a/p specifier can use lower, upper, or mixed case, and
the result is displayed accordingly.
ampm Uses the 12-hour clock for the preceding h or hh specifier, and
displays the contents of the TimeAMString global variable for any
hour before noon, and the contents of the TimePMString global
variable for any hour after noon.
/ Displays the date separator character given by the DateSeparator
global variable.
: Displays the time separator character given by the TimeSeparator
global variable.
'xx' Characters enclosed in single or double quotes are displayed as-is,
"xx" and do not affect formatting.
Format specifiers may be written in upper case as well as in lower case
letters--both produce the same result.
If the string given by the Format parameter is empty, the date and time
value is formatted as if a 'c' format specifier had been given.
The following example:
S := FormatDateTime('"The meeting is on" dddd, mmmm d, yyyy, ' +
'"at" hh:mm AM/PM', StrToDateTime('2/15/95 10:30am'));
assigns 'The meeting is on Wednesday, February 15, 1995 at 10:30 AM' to
the string variable S. }
function FormatDateTime(const Format: string; DateTime: TDateTime): string;
{ DateTimeToString converts the date and time value given by DateTime using
the format string given by Format into the string variable given by Result.
For further details, see the description of the FormatDateTime function. }
procedure DateTimeToString(var Result: string; const Format: string;
DateTime: TDateTime);
{ System error messages }
function SysErrorMessage(ErrorCode: Integer): string;
{ Initialization file support }
function GetLocaleStr(Locale, LocaleType: Integer; const Default: string): string;
function GetLocaleChar(Locale, LocaleType: Integer; Default: Char): Char;
{ GetFormatSettings resets all date and number format variables to their
default values. }
procedure GetFormatSettings;
{ Exception handling routines }
function ExceptObject: TObject;
function ExceptAddr: Pointer;
function ExceptionErrorMessage(ExceptObject: TObject; ExceptAddr: Pointer;
Buffer: PChar; Size: Integer): Integer;
procedure ShowException(ExceptObject: TObject; ExceptAddr: Pointer);
procedure Abort;
procedure OutOfMemoryError;
procedure Beep;
{ MBCS functions }
{ LeadBytes is a char set that indicates which char values are lead bytes
in multibyte character sets (Japanese, Chinese, etc).
This set is always empty for western locales. }
var
LeadBytes: set of Char = [];
(*$EXTERNALSYM LeadBytes*)
(*$HPPEMIT 'namespace Sysutils {'*)
(*$HPPEMIT 'extern PACKAGE System::Set<Byte, 0, 255> LeadBytes;'*)
(*$HPPEMIT '} // namespace Sysutils'*)
{ ByteType indicates what kind of byte exists at the Index'th byte in S.
Western locales always return mbSingleByte. Far East multibyte locales
may also return mbLeadByte, indicating the byte is the first in a multibyte
character sequence, and mbTrailByte, indicating that the byte is the second
in a multibyte character sequence. Parameters are assumed to be valid. }
function ByteType(const S: string; Index: Integer): TMbcsByteType;
{ StrByteType works the same as ByteType, but on null-terminated PChar strings }
function StrByteType(Str: PChar; Index: Cardinal): TMbcsByteType;
{ ByteToCharLen returns the character length of a MBCS string, scanning the
string for up to MaxLen bytes. In multibyte character sets, the number of
characters in a string may be less than the number of bytes. }
function ByteToCharLen(const S: string; MaxLen: Integer): Integer;
{ CharToByteLen returns the byte length of a MBCS string, scanning the string
for up to MaxLen characters. }
function CharToByteLen(const S: string; MaxLen: Integer): Integer;
{ ByteToCharIndex returns the 1-based character index of the Index'th byte in
a MBCS string. Returns zero if Index is out of range:
(Index <= 0) or (Index > Length(S)) }
function ByteToCharIndex(const S: string; Index: Integer): Integer;
{ CharToByteIndex returns the 1-based byte index of the Index'th character
in a MBCS string. Returns zero if Index or Result are out of range:
(Index <= 0) or (Index > Length(S)) or (Result would be > Length(S)) }
function CharToByteIndex(const S: string; Index: Integer): Integer;
{ IsPathDelimiter returns True if the character at byte S[Index]
is '\', and it is not a MBCS lead or trail byte. }
function IsPathDelimiter(const S: string; Index: Integer): Boolean;
{ IsDelimiter returns True if the character at byte S[Index] matches any
character in the Delimiters string, and the character is not a MBCS lead or
trail byte. S may contain multibyte characters; Delimiters must contain
only single byte characters. }
function IsDelimiter(const Delimiters, S: string; Index: Integer): Boolean;
{ IncludeTrailingBackslash returns the path with a '\' at the end.
This function is MBCS enabled. }
function IncludeTrailingBackslash(const S: string): string;
{ ExcludeTrailingBackslash returns the path without a '\' at the end.
This function is MBCS enabled. }
function ExcludeTrailingBackslash(const S: string): string;
{ LastDelimiter returns the byte index in S of the rightmost whole
character that matches any character in Delimiters (except null (#0)).
S may contain multibyte characters; Delimiters must contain only single
byte non-null characters.
Example: LastDelimiter('\.:', 'c:\filename.ext') returns 12. }
function LastDelimiter(const Delimiters, S: string): Integer;
{ AnsiCompareFileName supports DOS file name comparison idiosyncracies
in Far East locales (Zenkaku). In non-MBCS locales, AnsiCompareFileName
is identical to AnsiCompareText. For general purpose file name comparisions,
you should use this function instead of AnsiCompareText. }
function AnsiCompareFileName(const S1, S2: string): Integer;
{ AnsiLowerCaseFileName supports lowercase conversion idiosyncracies of
DOS file names in Far East locales (Zenkaku). In non-MBCS locales,
AnsiLowerCaseFileName is identical to AnsiLowerCase. }
function AnsiLowerCaseFileName(const S: string): string;
{ AnsiUpperCaseFileName supports uppercase conversion idiosyncracies of
DOS file names in Far East locales (Zenkaku). In non-MBCS locales,
AnsiUpperCaseFileName is identical to AnsiUpperCase. }
function AnsiUpperCaseFileName(const S: string): string;
{ AnsiPos: Same as Pos but supports MBCS strings }
function AnsiPos(const Substr, S: string): Integer;
{ AnsiStrPos: Same as StrPos but supports MBCS strings }
function AnsiStrPos(Str, SubStr: PChar): PChar;
{ AnsiStrRScan: Same as StrRScan but supports MBCS strings }
function AnsiStrRScan(Str: PChar; Chr: Char): PChar;
{ AnsiStrScan: Same as StrScan but supports MBCS strings }
function AnsiStrScan(Str: PChar; Chr: Char): PChar;
{ StringReplace replaces occurances of <oldpattern> with <newpattern> in a
given string. Assumes the string may contain Multibyte characters }
type
TReplaceFlags = set of (rfReplaceAll, rfIgnoreCase);
function StringReplace(const S, OldPattern, NewPattern: string;
Flags: TReplaceFlags): string;
{ WrapText will scan a string for BreakChars and insert the BreakStr at the
last BreakChar position before MaxCol. Will not insert a break into an
embedded quoted string (both ''' and '"' supported) }
function WrapText(const Line, BreakStr: string; BreakChars: TSysCharSet;
MaxCol: Integer): string; overload;
function WrapText(const Line: string; MaxCol: Integer = 45): string; overload;
{ FindCmdLineSwitch determines whether the string in the Switch parameter
was passed as a command line argument to the application. SwitchChars
identifies valid argument-delimiter characters (i.e., "-" and "/" are
common delimiters). The IgnoreCase paramter controls whether a
case-sensistive or case-insensitive search is performed. }
function FindCmdLineSwitch(const Switch: string; SwitchChars: TSysCharSet;
IgnoreCase: Boolean): Boolean;
{ FreeAndNil frees the given TObject instance and sets the variable reference
to nil. Be careful to only pass TObjects to this routine. }
procedure FreeAndNil(var Obj);
{ Interface support routines }
function Supports(const Instance: IUnknown; const Intf: TGUID; out Inst): Boolean; overload;
function Supports(Instance: TObject; const Intf: TGUID; out Inst): Boolean; overload;
{ Package support routines }
{ Package Info flags }
const
pfNeverBuild = $00000001;
pfDesignOnly = $00000002;
pfRunOnly = $00000004;
pfIgnoreDupUnits = $00000008;
pfModuleTypeMask = $C0000000;
pfExeModule = $00000000;
pfPackageModule = $40000000;
pfProducerMask = $0C000000;
pfV3Produced = $00000000;
pfProducerUndefined = $04000000;
pfBCB4Produced = $08000000;
pfDelphi4Produced = $0C000000;
pfLibraryModule = $80000000;
{ Unit info flags }
const
ufMainUnit = $01;
ufPackageUnit = $02;
ufWeakUnit = $04;
ufOrgWeakUnit = $08;
ufImplicitUnit = $10;
ufWeakPackageUnit = ufPackageUnit or ufWeakUnit;
{ Procedure type of the callback given to GetPackageInfo. Name is the actual
name of the package element. If IsUnit is True then Name is the name of
a contained unit; a required package if False. Param is the value passed
to GetPackageInfo }
type
TNameType = (ntContainsUnit, ntRequiresPackage);
TPackageInfoProc = procedure (const Name: string; NameType: TNameType; Flags: Byte; Param: Pointer);
{ LoadPackage loads a given package DLL, checks for duplicate units and
calls the initialization blocks of all the contained units }
function LoadPackage(const Name: string): HMODULE;
{ UnloadPackage does the opposite of LoadPackage by calling the finalization
blocks of all contained units, then unloading the package DLL }
procedure UnloadPackage(Module: HMODULE);
{ GetPackageInfo accesses the given package's info table and enumerates
all the contained units and required packages }
procedure GetPackageInfo(Module: HMODULE; Param: Pointer; var Flags: Integer;
InfoProc: TPackageInfoProc);
{ GetPackageDescription loads the description resource from the package
library. If the description resource does not exist,
an empty string is returned. }
function GetPackageDescription(ModuleName: PChar): string;
{ InitializePackage Validates and initializes the given package DLL }
procedure InitializePackage(Module: HMODULE);
{ FinalizePackage finalizes the given package DLL }
procedure FinalizePackage(Module: HMODULE);
{ RaiseLastWin32Error calls the GetLastError API to retrieve the code for }
{ the last occuring Win32 error. If GetLastError returns an error code, }
{ RaiseLastWin32Error then raises an exception with the error code and }
{ message associated with with error. }
procedure RaiseLastWin32Error;
{ Win32Check is used to check the return value of a Win32 API function }
{ which returns a BOOL to indicate success. If the Win32 API function }
{ returns False (indicating failure), Win32Check calls RaiseLastWin32Error }
{ to raise an exception. If the Win32 API function returns True, }
{ Win32Check returns True. }
function Win32Check(RetVal: BOOL): BOOL;
{ Termination procedure support }
type
TTerminateProc = function: Boolean;
{ Call AddTerminateProc to add a terminate procedure to the system list of }
{ termination procedures. Delphi will call all of the function in the }
{ termination procedure list before an application terminates. The user- }
{ defined TermProc function should return True if the application can }
{ safely terminate or False if the application cannot safely terminate. }
{ If one of the functions in the termination procedure list returns False, }
{ the application will not terminate. }
procedure AddTerminateProc(TermProc: TTerminateProc);
{ CallTerminateProcs is called by VCL when an application is about to }
{ terminate. It returns True only if all of the functions in the }
{ system's terminate procedure list return True. This function is }
{ intended only to be called by Delphi, and it should not be called }
{ directly. }
function CallTerminateProcs: Boolean;
function GDAL: LongWord;
procedure RCS;
procedure RPR;
{ HexDisplayPrefix contains the prefix to display on hexadecimal
values - '$' for Pascal syntax, '0x' for C++ syntax. This is
for display only - this does not affect the string-to-integer
conversion routines. }
var
HexDisplayPrefix: string = '$';
{ The GetDiskFreeSpace Win32 API does not support partitions larger than 2GB
under Win95. A new Win32 function, GetDiskFreeSpaceEx, supports partitions
larger than 2GB but only exists on Win NT 4.0 and Win95 OSR2.
The GetDiskFreeSpaceEx function pointer variable below will be initialized
at startup to point to either the actual OS API function if it exists on
the system, or to an internal Delphi function if it does not. When running
on Win95 pre-OSR2, the output of this function will still be limited to
the 2GB range reported by Win95, but at least you don't have to worry
about which API function to call in code you write. }
var
GetDiskFreeSpaceEx: function (Directory: PChar; var FreeAvailable,
TotalSpace: TLargeInteger; TotalFree: PLargeInteger): Bool stdcall = nil;
{ SafeLoadLibrary calls LoadLibrary, disabling normal Win32 error message
popup dialogs if the requested file can't be loaded. SafeLoadLibrary also
preserves the current FPU control word (precision, exception masks) across
the LoadLibrary call (in case the DLL you're loading hammers the FPU control
word in its initialization, as many MS DLLs do)}
function SafeLoadLibrary(const Filename: string;
ErrorMode: UINT = SEM_NOOPENFILEERRORBOX): HMODULE;
{ Thread synchronization }
{ TMultiReadExclusiveWriteSynchronizer minimizes thread serialization to gain
read access to a resource shared among threads while still providing complete
exclusivity to callers needing write access to the shared resource.
(multithread shared reads, single thread exclusive write)
Reading is allowed while owning a write lock.
Read locks can be promoted to write locks.}
type
TActiveThreadRecord = record
ThreadID: Integer;
RecursionCount: Integer;
end;
TActiveThreadArray = array of TActiveThreadRecord;
TMultiReadExclusiveWriteSynchronizer = class
public
constructor Create;
destructor Destroy; override;
procedure BeginRead;
procedure EndRead;
procedure BeginWrite;
procedure EndWrite;
end;
implementation