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Text File | 1992-12-20 | 53.0 KB | 2,155 lines

********************************************************************* Unit Tbase.TPU ********************************************************************* Introduction This is the main unit of my goal- Defining Objects to handle Dbase III and FOXPRO compatible files. The old existing Programs did not provide satisfactory performance to me. Tbase provides facilities to Create Dbase files, Manipulation on FIeld Structure and Manipulations on Data. Tbase allows you to supply Fieldname as argument ( string ) in methods. For example, FieldData( 'Cust_No' ) will give you the data of CUST_NO in the current record ( if such a field exists.. ) For those who are familiar with using Field numbers in the older programs, Tbase provide Methods that accepts field numbers too. The consistency in these procedures are: any method that accepts a field name string as an argument has its counterpart with the same structure but with Field number in place of Field Name. The name of the method adds a MY in its identifier. For example, FieldData accepts Field name string while MYFieldData accept Field Number as Argument. Validity Checks are performed in many methods. If the check fails anywhere, the error variable DbError is set to an error number and a Bleep sound occurs. No Screen Display is reported nor does the program abort. The only case the program is aborted is when initializing ( Opening ) a Dbase Object. The reason for this non-screen report is to avoid the disturbance when using graphical environment. Whenever the Dberror is set to a nonzero value ( due to an error ) any other succeeding calls to any method will be ignored causing non-Update of your data or even loose. So, if your program does make a bleep anywhere, debug it and correct the problem. To refer the error and to know causing factor, Refer to the table below for meaning of the DbError values. A call to LastDbError will return the error value and Clears the DbError. Dberror is internal to Object. Hence an error in one Dbase object does not affect the other Dbase objects method call. DbError Error description 0 No Error. 1 Header Description corrupted. 2 Disk read Error. 3 Dbase File Not Found. 4 Not Enough Memory to allocate. 5 File Access Denied or could not open file. 6 Could not Write to disk.( Sector problem? Disk full?) 7 Field Type is not Numeric. 9 Field name does not exits or Field Number out of range. 8 Not valid date. 10 Data does not match with Field Type. 11 -- 12 -- 13 Could not Create file. 14 Dbase file Not Empty. 15 Invalid Field Type. 16 Field limit exceeds. Only 255 fields are allowed. 17 Divisor Field is zero. When I encounter more error situations, I will add more error values. If you find anything.. report them to me..please. ********************************************************************* Tbase unit Procedures and Functions ********************************************************************* Add, MyAdd Description Adds two numeric fields and returns real result. Syntax Function Add( Field1, Field2 : String) : Real; Function MyAdd( Fno1 , Fno2 : Byte ) : Real; Remarks Field1 and Field2 are the names of the fields. Exits with Bleep if Fields are not numeric and the result is set to zero. See Also Increment, Decrement, Multiply, Mul, Divide and their MYs ---------------------------------------------------------- AddBlankRecs Description Appends a number of Blank records to the Dbase file. Syntax Procedure AddBlankRecs( NumRecs : LongInt); See Also AppendBlank , PutDbRec, ClearMemRec ---------------------------------------------------------- AddDbRec Description Appends the Memory record to Dbase file. Syntax Procedure AddDbRec; Remarks The difference between AppendBlank and AddDbRec is that AddDbrec Dumps the memory record to file while AppendBlank Will clear the memory and writes to disk Warning If the memory record is marked for deletion,the added record is also written as marked. Undelete before writing. See Also AppendBlank, AddBlankRecs ---------------------------------------------------------- AppendBlank Description Adds a Blank Record to Dbase file Syntax Procedure AppendBlank; Warning Memory Record will be lost. See Also AddBlankRecs ---------------------------------------------------------- Average , MyAverage Description Calculates the Average of a numeric field Syntax Function Average(Field1 : String) : Real; Remarks Checks for Numeric type and for Number of records is > 0. If check fails Average is reset to 0.0 and bleeps See Also Sum , MySum ---------------------------------------------------------- ChangeField , MyChangeField Description Changes the Description of a Field Structure on an EMPTY Dbase File. Syntax Procedure ChangeFIeld( Field1, Fname: String; Ftype: Char; Flen, Fdec : Byte ); Remarks Memory record size is adjusted if needed. Checks for valid type Character. C,N,F,D,L are supported. Field length is automatic for D and L type. Ignores any length in this case Warning Maximum Field Length is 254. Though 255 is accepted, Foxpro and other Dbase KITs do not identify it as a Dbase File. See Also AddField, DeleteField, FieldName, FieldNo, FieldType ---------------------------------------------------------- CopyStructureTo Description Creates another Empty Dbase File with the specified name copying the current file Structure. Syntax Procedure CopyStructureTo(Fname: String); Remarks Only the Header is copied. Not the Data of the Dbase file. The new Empty Dbase file must be explicitly opened for any addition of Data. See Also CreateDbaseFile, DeleteDbaseFile ---------------------------------------------------------- ClearMemRec Description Clears the memory record by Space Characters. Syntax Procedure ClearMemRec; Remarks The old Memory record is written to the current record if Autosave is TRUE See Also AppendBlank ---------------------------------------------------------- DbBof Description Return True if the current Record is the first or nil (in case of no record are found). Syntax Function DbBof : Boolean; See Also DbEof ---------------------------------------------------------- DbDelete Description Marks the record as Deleted. Syntax Procedure DbDelete; Remarks Mark not written to file immediately. Autosave will do that. If Autosave is OFF, manually update the record to disk. See Also Recall , Pack, Zap ---------------------------------------------------------- DbEof Description Returns TRUE if the current record is the last record Syntax Function DbEof : Boolean; See Also DbBof ---------------------------------------------------------- DbfName Description Returns the Dbase filename opened in the object. Syntax Function DnfName : String; Remarks Only the name with extension is returned. not the path. See Also DbfDir ---------------------------------------------------------- DbfDir Description Returns the Path of the Dbase file. Syntax Function DbfDir : String; Remarks Only the path that you have given when initializing the object is returned. See Also DbfName ---------------------------------------------------------- Dbreset Description Resets the Dbase file as newly initialized. Syntax Procedure DbReset; Remarks Current record is set to 1 or 0 (if no data) Warning Memory record is lost if not written to file. See Also Init ---------------------------------------------------------- Decrement , MyDecrement Description Subtracts a real value from a specified field and returns real result. Syntax Function Decrement( Field1: String; by : real ): Real ; Function MyDecrement(Fno: Byte; by : Real ) : Real ; Remarks Checks for Numeric fields and bleeps for warning. Negative values in 'by' will ( ofcourse ) be added. Warning Does not check for overflow. See Also Increment , add, Sub and their MY counterparts. ---------------------------------------------------------- Deleted Description Returns True if the current record is marked for deletion Syntax Function Deleted : Boolean; See Also DbDelete, Recall , Pack, Zap ---------------------------------------------------------- DeleteField, MyDeleteField Description Removes a field from the structure of an EMPTY Dbase file. Syntax Procedure DeleteField( Field1 : String ); Procedure MyDeleteField( FNo : Byte ); Remarks Field Numbering is reassigned bringing the later fields one step closer. Memory record size is adjusted. If field1 is not found Dberror is set to 9 ( Fieldno out of range ) See Also AddField, ChangeField, CopyStructureTo, CreateDbaseFile ---------------------------------------------------------- AddField, MyAddField Description Adds a new Field Description to the Dbase Structure. Syntax Procedure AddField(Fname:String; Ftype:Char;Flen,Fdec:Byte); Procedure MyAddfield(Fno:Byte;Ftype:Char; Flen,Fdec : Byte); Remarks Memory Record size is Adjusted. Checks for valid Fieldtype. Flen and Fdec are length and decimal sizes. Flen and Fdec are ignored for D,L type. Fdec is ignored for non-numeric. Warning Allowed number of Fields are 255. For Foxpro compatibility, keep the total record size not exceed 4000bytes. See Also ChangeField , DeleteField and their MY counterparts. ---------------------------------------------------------- Divide, MyDivide Description Divides the first Numeric Field value by the second and returns real. Syntax Function Divide( Field1,Field2 : String) : Real ; Function MyDivide( Fno1, Fno2 : Byte ) : Real ; Remarks Checks whether the second field data is zero. If so, the result is set to 0.0. Checks also for numeric Data in both fields. Call LastDberror for error value. See Also Multiply, add, Sub and their MY variations ---------------------------------------------------------- Done Description Closes the Dbase File and its Object. Syntax Destructor Done; Remarks Frees all the associated memory. Use it with dispose. Eg. Dispose( MyDbf , Done ) ; Warning If not used with Dispose, memories are not freed and the Dbase file is NOT closed causing loss of Data. See Also Init ---------------------------------------------------------- FieldCount Description Returns the Number of Fields in the Dbase file. Syntax Function FieldCount : Byte; See Also FieldName, FieldNo, FieldSize, FieldType ---------------------------------------------------------- FieldData, MyFieldData Description Returns the Data of the Specified field of current record. Syntax Function FieldData( Field1 : String ) : String ; Function MyFieldData(Fno : Byte ) : String ; Remarks If FIeld1 not found Dberror 9 is returned. Data is NOT Trimmed. Use Trim, Ltrim or Rtrim in DBStr which trims the trailing and leading spaces and nulls. Warning For Date field, the date is formatted according to the current format setting. See Also Replace , MyReplace ---------------------------------------------------------- FieldName Description Returns the Name of the specified field number. Syntax Function FieldName(Fno : Byte ) : String; Remarks Checks for Fno range (1..FieldCount). FieldName Returned is Trimmed ( Unlike FIeldData ). Null String Returned if any failure to validity check. Warning Returned name is Upper cased. Eg. CUST_NO See Also FieldNo, FieldSize, FieldType, FieldCount ---------------------------------------------------------- FieldNo Description Returns the Ordinal number of the Specified field name. Syntax Function FieldNo ( Field1: String ) : Byte ; Remarks Field1 can be of any case having trailing and leading spaces or nulls. The same theory applies to ALL methods having field name string as argument. eg. ' cUst_NO ' is valid. Warning 0 is returned if the name is not valid or not found in the structure. See Also FIeldName, FIeldSize, FieldType, FIeldCount ---------------------------------------------------------- FieldSize, MyFieldSize Description Returns the Field length of an specified field name. Syntax Function FieldSize ( Field1 : String ) : Byte ; Function MyFIeldSize( Fno : Byte ) : Byte ; Warning 0 is returned if Field name or number is invalid. See Also FieldName, FieldType, FieldNo, FieldCount, FieldDec ---------------------------------------------------------- FieldType, MyFieldType Description Returns the Type of the specified field Name or Number. Syntax Function FieldType( Field1 : String ) : Char ; Function MyFieldType(Fno : String ) : Char ; Remarks Returned Characters are : C - Character; N - Numeric F - Floating; D - Date; L - Logical; M - Memo. Warning Although 'M' is identified, no support is provided in this version. See Also FiledName, FieldSize, FieldNo, FieldCount, FieldDec ---------------------------------------------------------- FlushDb Description Saves the Memory record to the current record. Syntax Procedure FlushDb; Remarks No need to use this if autosave is ON ( TRUE ). Warning Record in the current record is overwritten. (Who Cares !!) See Also PutDbRec, GetDbRec, SetAutoSave ---------------------------------------------------------- GetDbRec Description Loads the specified recordNumber into memory record. Syntax Procedure GetDbRec( RecordNumber : LongInt) ; Remarks RecordNumber becomes current record. If AutoSave is ON, the previous memory is Flushed to its position if modified. Checks for Valid RecordNumber ( 1..RecCount ) Warning Exception: Memory record is not updated when loading the same record.Eg. GetDbRec(RecNO) will cancel any last update. See Also FlushDb, PutDbRec, SetAutoSave ---------------------------------------------------------- GetFieldHeaders ( Internal ) Description Reads the Field header to memory ( not to Memory record ) Syntax Procedure GetFieldHeaders; Remarks Use this if you feel the Field methods give improper results This will not happen anyway.. But just to be on safe side. I use this internally. See Also ReadHeader, WriteHeader, WriteFields ( all internal ) ---------------------------------------------------------- GoBottom Description Moves to the last record of the Dbase file and loads it into memory record. Syntax Procedure GoBottom; Remarks Ignores if No record found.Previous memory record is flushed if Autosave is ON. Warning If AutoSave is OFF, the prevoius memory is lost. Manually Flush the memory record if so. See Also GoTop, NextRec, PrecRec, Skip, Locate ---------------------------------------------------------- GoTop Description Positions to the First record of the Dbase file and loads it into memory record. Syntax Procedure GoTop; Remarks Ignores if no record is found. Prevoius memory record is flushed if AutoSave is ON. Warning If Autosave is OFF, the prevoius memory record is lost. Manually Flush the memory record if so. See Also GoBottom, NextRec, PrevRec, Skip, Locate ---------------------------------------------------------- Increment, MyIncrement Description Adds a real value to specified field data in the current record and returns real. Syntax Function Inrement( Field1 : String; By : Real ) : Real ; Function MyIncrement( Fno : Byte ; By : real ) : Real ; Remarks Field1 is the FieldName of the numeric field.'By' is the real value incremented.Ignores if FielName is not of Numeric type and returns 0 with error bleep. See Also Decrement, Add, Sub, SUM, Average, Mul, Multiply ---------------------------------------------------------- Init Description Opens the Dbase file loading the necessary information into memory. Syntax Constructor Init( Fname : String66) ; Eg. NEW( MyDbf, init('MyDb.Dbf') ); Remarks Allocates minimum memory to accommodate information. More fields means more memory. See Also Done ---------------------------------------------------------- LastDbError Description Returns the Last Errorvalue occurred and clears it to zero. Syntax Function LastDberror : Byte ; Remarks Useful to check the error occurred. If the DBerror is not cleared by this call, All calls to any method will be ignored. This applies to all methods in the Object. Warning Exceptions are Init and Done. ---------------------------------------------------------- Locate , MyLocate Description Sequentially Searches for a string in a specified field and loads the record into memory record if found. Syntax Procedure Locate(Field1: String; SearchStr : String ); Procedure MyLocate(Fno : Byte ; SearchStr : String ); Remarks The exact search string is searched for match with Trailing and leading spaces. If found, the record is loaded into memory and the Object local variable Found is set to TRUE. Warning If the field Data is filled with Null for trailing spaces, searching with Trailing spaces may not work. See Also GetDbRec ---------------------------------------------------------- Lupdate Description Returns the Date that the Dbase file is Last modified. Syntax Function Lupdate : String; Remarks The Date Format is affected by the SetDateFormat in DbDate Unit. Refer DbDate unit procedures and function for allowed formats and Default format. ---------------------------------------------------------- Mul, MyMul Description Multiplies two numeric fields and returns real. Syntax Function Mul(Field1, Field2: String ) : Real ; Function MyMul( Fno1, Fno2 : Byte ) : Real ; Remarks Checks for validity if Numeric Field type. Does Not Check for overflow. ( may be in future versions) See Also Add, Increment, Sub, Decrement, Divide, SUM, Average ---------------------------------------------------------- Multiply, MyMultiply Description Multipies a Numeric FieldData with a real number and returns real. Syntax Function Multiply( Field1 : String; By : real ): Real; Function MyMultiply( Fno1 : Byte ; By : real ): Real; Remarks Checks for Numeric fields. Returns 0 if not valid. Does not check for Overflow. See Also Add, Increment, Decrement, Sub, Divide, Mul, SUM, Average ---------------------------------------------------------- NextRec Description Moves to the next record and loads it into memory record. Syntax Procedure NextRec; Remarks If Autosave is ON the previous memory record is flushed. See Also Skip, PrevRec, GoTop, GoBottom ---------------------------------------------------------- Pack Description Removes all the marked records for deletion. You no longer have any deleted records. Syntax Procedure Pack; Remarks Current record is pointed to the last record. Ignores if no record is found deleted ( Ofcourse !) Slow as complete read-write occurs. Warning Memory record will be lost if AutoSave is OFF. No recovery possible after packed. See Also Zap, DbDelete, Recall ---------------------------------------------------------- PutDbRec Description Writes the memory record to specified recordNumber. Syntax Procedure PutDbRec( RecordNumber : LongInt ); Remarks Different than FlushDB in the sense that it writes the memory record to a different location. Flushes the previous memory record to its position if changed. Warning If the memory record is marked for deletion it is written as deleted. Recall if you want to. See Also GetDbRec, FlushDb ---------------------------------------------------------- PrevRec Description Moves to the previous record and loads it into memory record Syntax Procedure PrevRec; Remarks Ignores if no record found.Previous memory record is written to its position if Autosave is ON. See Also NextRec, Skip, GoTop, GoBottom ---------------------------------------------------------- Recall Description Undeletes the current record if marked. Syntax Procedure Recall; Remarks Does not immediately writes to file. When moving to another record, memory is flushed if autosave is ON. Warning If AutoSave is OFF, manually Flush the memory record. See Also DbDelete, Pack ---------------------------------------------------------- RecCount Description Returns the Number of Records in the DBase file. Syntax Function RecCount : LongInt ; See Also RecNo ---------------------------------------------------------- RecNo Description Returns the Current record number positioned. Syntax Function RecNo : LongInt; See Also RecCount , FieldCount ---------------------------------------------------------- RecSize Description Returns the Record size of a record in Dbase. Syntax Function RecSize : word; Remarks This size will be adjusted if field structure is modified by addfield, changefield or deletefield. Warning If Recsize >4000 bytes, the Dbase file will NOT be Dbase III and foxPro compatible. But Tbase3 will recognize. ---------------------------------------------------------- ReadHeader ( Internal ) Description Reads the Header description of the Dbase file. Syntax Procedure ReadHeader; Remarks Checks for valid Header. I use this Internally. See Also ReadFieldHeaders, WriteHeader, WriteFields ---------------------------------------------------------- Replace, MyReplace Description Replaces a FIeldData with a Formatted string Data. Syntax Procedure Replace( Field1: String; InData : String ); Procedure MyReplace(Fno : Byte ; InData : String ); Remarks This is the comprehensive replace for all type of fields. Checks if the Type fits with the Indata format.For dateType, Checks for valid date also. Numeric are reformatted to fit. Warning Date field requires a formatted date String according to the current format setting. See Also ReplaceAll, ReplNum, ReplDate, ReplStr and their MY versions ---------------------------------------------------------- ReplaceAll, MyReplaceAll Description Replaces all records' in specified field with indata string. Syntax Procedure ReplaceAll(Field1: String; Indata : String ); Procedure MyReplaceAll(Fno1: Byte ; Indata : String ); Remarks Comprehensive as Replace. See description for replace above. Checks for valid field to match data. Numeric data is reformatted to fit with fieldlen and fieldDec. Warning Date Format requirs a formatted Date string. See Also Replace, ReplNum, ReplDate, ReplStr and their MY versions ---------------------------------------------------------- ReplNum, MyReplNum Description Replaces a Numeric Field data with a real number. Syntax Procedure ReplNum( Field1 : String; Re : real ) ; Procedure MyReplNum( Fno1 : Byte ; Re : real ) ; Remarks Checks for Numeric field type, Formats the Real number according to fieldsize, and field Decimal. Warning Some Decimal accuracy maybe lost if the integral part of the number is beyond the limit. See Also Replace, ReplDate, ReplStr, ReplaceAll and their MY versions ---------------------------------------------------------- ReplDate, MyReplDate Description Replaces a Date field with the Indate Data. Syntax Procedure ReplDate(Field1 : String; Indate : Date ) ; Procedure MyReplDate(Fno1 : Byte ; InDate : Date ) ; Remarks Date Datatype is defined in DbDate. Checks for valid Date and Date FieldType. Ignores if Fails. Formats the Date to the Date String form for the date field. Warning Year in Date record type MUST be in ccxx form. eg. 1993 See Also DbDate Unit ---------------------------------------------------------- ReplStr, MyReplStr ( Internal) Description Replaces ANY field by a String data. Syntax Procedure ReplStr( Field1: String; Instr : String ); Procedure MyReplStr(Fno1 : Byte ; Instr : String ); Remarks No checking is done during the replace. Only it trims the instr to fit with the Fieldsize. Use Replace if you want to replace string fields. Warning Do not use this as you might write wrong Data into a wrong FieldType. Internal See Also Replace, ReplaceAll, ReplNum, ReplStr ---------------------------------------------------------- Save Description Writes all the appropriate memory date to file. Syntax Procedure Save; Remarks Almost like flush. But writes the header also. Only for security reason if you are aware of any power failure. See Also FlushDb ---------------------------------------------------------- Skip Description Moves to the next record and loads it into memory. Syntax Procedure Skip; Remarks Excactly the same as NextRec. Just to make our old Dbase fans happy!. See Also NextRec, prevRec, GoTop, GoBottom ---------------------------------------------------------- Sub, MySub Description Subtracts Field2 Numeric data from Field1 Numeric Data and returns real. Syntax Function Sub(Field1, field2 : String ) : Real ; Function MySub(Fno1, Fno2 : Byte ) : Real; Remarks Checks for Numeric fields. Ignores if either one fails and returns zero. See Also Add, Mul, Divide , Inrement, Decrememnt, SUM, Average ---------------------------------------------------------- SUM , MySUM Description Adds all the data in the specified Numeric field and returns real. Syntax Function SUM ( Field1 : String ) : Real ; Function MySUM( Fno1 : Byte ) : Real ; Remarks Checks for Numeric Field Type. Ignores if not and returns 0 as result. Does NOT check for overflow. ( In the future ) See Also Add, Sub, Mul, Divide, Increment, Decrement, Average ---------------------------------------------------------- WriteHeader ( internal ) Description Writes the Header to Dbase file. Syntax Procedure WriteHeader; Remarks Last modified date is updated with the header. See Also Readheader, WriteFields, GetFieldHeaders ---------------------------------------------------------- WriteFields ( internal ) Description Writes the field structure description to the disk. Syntax Procedure WriteFields; See Also GetFieldHeaders ---------------------------------------------------------- Zap Description Erases all data in the Dbase file. Syntax Procedure Zap; Remarks Permanently erases all data in the file. Complete recovery is not possible. A partial recovery is tried in this version. Warning Think Twice before you Zap!! See Also Pack, Recover ---------------------------------------------------------- DisplayFields Description Just Displays the fieldnames on the screen for reference. Syntax Procedure DisplayFields; Remarks Not much format is is provided as display is NOT the purpose of the Object. Use FieldName, FieldNo, FieldType, FieldSize and FieldDec for field description detail Warning Does not display in Graphical environment. See Also FieldName, FieldSize, FieldType, FieldNo, FieldDec ---------------------------------------------------------- FieldDec , MyFieldDec Description Returns the Decimal value of a Numeric field. Syntax Function FieldDec (Field1: String ) : Byte ; Function MyFieldDec( Fno : Byte ) : Byte ; Remarks Zero is returned if the Field Type is not Numeric. See Also FieldName, FieldSize, FieldType, FieldNo, FieldCount ---------------------------------------------------------- Autosaved ( Internal ) Description Flushes the memory record whenever needed if Autosave is ON. Syntax Procedure Autosaved; Remarks It writes the memory record to file only if any changes have been made since last flush or load. This minimizes the disk write when autosave is ON. See Also SetAutosave ---------------------------------------------------------- SetAutoSave Description Sets the autosave status to ON or OFF. Syntax Procedure SetAutosave( auto : Boolean ) ; Remarks If auto is TRUE, Autosave is set to ON otherwise OFF. Default is ON. Warning If autosave is set to OFF, any update to memory record MUST be manually saved to file. ---------------------------------------------------------- ********************************************************************* Unit DbEdit ********************************************************************* Introduction This unit handles the field and variable editing. GET and MyGET prepares for editing of a dbase file fields while SAY prepares for a variable edit. All these three procedures can be mixed in a group of Editing. Dbread activates the editing. Dbread Updates the Fields automatically upon completing its job. If the fields are from different Dbase files, they are updated accordingly. Variables are kept in their names. Each edit item can have its own color. Just set the edit color for the next item by SetEditColor. Each Edit item can have its own help too. All you have to do is to write a FAR rpocedure that displays Help or anything you want.Then, Set the help procedure through SetHelpProc for the next edit item. Preesing F1 will call the assigned procedure. It is your responsibility to add fancy in that procedure. Eg. Open a winodow and close it. See My.Pas. The help procedure has no argument and ofcourse should be a far {$F+} procedure {$F-}. If no help is needed for an Item, Use SetHelpProc ( NoHelp ) ; If Crtl_Brk is pressed, Dbread simply exits the editing without updating the Fields. But Variables (SAY) have the effect of change. Field Type, Length and Field Decimal ( for numeric ) are needed for SAY to identify the editing behaviour. Use SetEditDecimal to Set decimal before calling SAY With numerical String. MYGET and GET assume their field type and decimal values from the field being editted. No Picture support is provided for now. ( Too much to ask ) DbEdit checks for the validity of the data for its type. Upon completing the edit, DbEdit sets a variable ReadExitCode a value according to the circumstance of the Exit. Different key press gives different values for ReadExitcode. This could be refered to take action according to the keypress. Following are the Keys and ReadExitCode for DbRead. Key ReadExitCode F10 3 PgUp 4 PgDn 5 Alt_X 6 Ctrl_N 7 Ctrl_Brk 8 Ctrl_PgUp 9 Ctrl_PgDn 10 Ctrl_X 11 Ctrl_End 12 Dbedit is exitted in either of the situations. 1. Pressing Enter when editting the last field or variable. ( ReadExitCode = 0 ) 2. Pressing Down arrow key when editing the last field or var ( ReadExitCode = 2 ) 3. Pressing any of the keys above from anywhere in editting. ( ReadexitCode as above) See my.Pas for how these exitcodes are used to take action. ********************************************************************* Set_Cursor Description Sets the Cursor size to specified size from bottom. Syntax Procedure Set_Cursor( n : Byte ) ; ---------------------------------------------------------- SetEditColor Description Sets the editing color pair for field line editor. Syntax Procedure SetEditColor( fcolor , bcolor : byte ); Remarks fcolor is the forground color and bcolor is background. Every field edit can have its own color pair. Just set the color just before a call to SAY. See Also Say , Dbread ---------------------------------------------------------- Arrow Description Reads a keypress and return ascii and scan code. Syntax Procedure Arrow( Var Ascii , scan : Byte ); Remarks Ctrl_Brk has no effect. But Returns Ascii = 3 and scan = 0. ---------------------------------------------------------- edit ( internal ) Description Allows Editing of a string variable. Syntax Function Edit(var Item : ReaderPtr ) : Word ; Remarks Returns various code values depending on the exit key. The standard editing keys have their own function. See My.Pas for more detail. Allows Editing according to Type. Warning When Date Field is editted, leaving the date Blank will replace the System Todays Date. See Also Say, DBread ---------------------------------------------------------- Say Description Prepares a variable for editing. Say is not a displayer. Differ With GET in Say only edits Variable. NOT fields. Syntax Procedure Say( x , y , Len : Word; s : PtrStr; Ftype : FieldTypes); Remarks x,y is the starting position, Len is the length of string, s is the POINTER to the editted string variable.Eg @name Ftype is the type of variable to treat as a field type. Warning Decimal size for Numeric type must be set through SetEditDecimal. See Also Get, DbRead ---------------------------------------------------------- Dbread Description Activates all the variables prepared for ediitting by SAY , GET and MyGET Syntax Procedure Dbread; Remarks Called once for a group of SAYs and GETs.Checks for validity of Data for FieldType. Does not allow moving to next field if the check fails. Warning Exits for many key combinations with various ReadEditCode. See my.Pas for more detail. See Also Say ---------------------------------------------------------- SetHelpProc Description Sets a procedure for an edit field for Help. Syntax Procedure SetEditProc( Help : HelpProc ); Remarks HelpProc is a Far procedure type with no arguments. You can assign help to each editted fields. See My.Pas. Default is NoHelp Warning If your HelpProcedure allocates any memory, make sure to deallocate them before exiting. See Also NoHelp ---------------------------------------------------------- NoHelp Description A null Help Procedure that does nothing. Syntax {$F+} Procedure NoHelp; {$F-} Remarks This is the Default Help procedure. An assignment to a user defined help procedure will be effective until it turned off Use SetHelpProc(Nohelp) to get back to Default. See Also SetHelpProc ---------------------------------------------------------- Get Description Prepares a Field of a Dbase File for editting. Handles Multiple Dbase files' Fields together. Syntax Procedure GET(x, y: Word; DbObj: DataObject; Field: String); Remarks DbObj is the pointer to the Dbase object. 'Field' is a Fiel in that object. You can give different Dbobj in a group of editting. They will be updated accordingly. Clever.. huh.. Warning If the Field name is not valid, a bleep warns. Take care at this point as the data will not be updated in this case. See Also SAY , DbRead ---------------------------------------------------------- MyGET Description Prepares a Field for Editting and updates to the proper data base file when editting finishes. Syntax Procedure MyGET ( x,y, Dbase : DataObject ; Fno : Byte ); Remarks This is just the My version of GET for those who uses the Field Number instead of FieldName itself. Or in otherwords, All the MY Versions are the TPDB fans. Warning If the Fno is out of range then the data will not be updated. ( Where to update? ) Thus you loose the editted data. See Also SAY , GET DbRead ---------------------------------------------------------- *********************************************************************** Unit DbDate.TPU *********************************************************************** Introduction This unit performs most of the operations on date. Conversion between the three type of date formats are provided. Thse three fields are: Field : The format that the Dbase file have date as Data. field format is of the form 'ccyymmdd'. eg. 19921223 Display : The format for display. This has many forms according to country. Following are the formats supported in this unit. French : dd/mm/yy German : dd.mm.yy Italian : dd-mm-yy British : dd/mm/yy American : mm/dd/yy Ansi : yy.mm.dd Pascal : The pascal format is the record containing the three fields Year, month and day with year in 19yy. Date = Record Year, Month , Day : Word ; End; I name Field for Field format; Format for Display format; Date for Pascal format to name the convertion procedures. Thus, FieldToFormat will convert the filed format to Display format; DateToField wil convert the Pascal format to Field Format and so on. SetDateFormat will set the current display format. *********************************************************************** Julian Description Returns the classic Julian number of a Date. Syntax Function Julian ( d : Date ) : LongInt; ---------------------------------------------------------- DaysBetween Description Returns the number of days between two dates. Syntax Function DaysBetween( d1, d2 : Date ) : LongInt; Warning Negative days are reported if d2 is earlier d1. See Also DateAfter ---------------------------------------------------------- MDY Description Formats a date to Month dd, 19yy format Syntax Function MDY( d : Date ) : String ; Remarks Example. const d : date = ( Year: 1992; Month:11; day:28); Begin Writeln( MDY( d ) ) End. result: November 28, 1992 See Also DateFormat ---------------------------------------------------------- DateToField Description Converts a date to a Dbase Date Field String type. Syntax Function DateToField( d : Date ) : String; Remarks The Dbase Date Format is : 19yymmdd Warning Checks valid date. Nul string returned if fails. See Also FieldToDate ---------------------------------------------------------- DateToFormat Description Formats a Date to a string format for display. Syntax Function DateToFormat( d : Date ) : Str8 ; Remarks The format wanted is selected through SetDateFormat. See Also DateToField, FieldToDate, FormatToDate, FieldToFormat ---------------------------------------------------------- SetDateFormat Description Sets the default date format for conversion. Syntax Procedure SetDateFormat( form : Byte ) ; Remarks Any conversion the returns or involves formatted date is affected by the current format. In Tbase unit, FieldData, Replace are affected. SAY in Dbedit is also affected. See Also FormatToDate, FormatToField, FieldToFormat, DateToFormat ---------------------------------------------------------- FieldToDate Description Converts a Dbase Date Format to a Pascal Date type. Syntax Procedure FieldToDate( s : String; Var d : date ); See Also DateToField ---------------------------------------------------------- DayofWeek Description Returns the Day of week in number for the specified date Syntax Function DayOfweek( d : Date ) : Word; Remarks The returned number is between 0 and 6 with 0 for Sunday. See Also NameOfWeek ---------------------------------------------------------- NameOfWeek Description Returns the name of week for the day. Syntax Function NameOfWeek( d : date ) : Str10 ; Remarks Sunday, Monday.. Etc See Also DayOfWeek ---------------------------------------------------------- DateAfter Description Returns the date after a certain days Syntax Procedure DateAfter( Var D : Date; days : LongInt ); Remarks Negative days willadvance the date as usual Warning The previous date will be lost. Be careful. ---------------------------------------------------------- Today Description Returns the Date of the System Clock in Date type Syntax Procedure Today ( Var d : day ); ---------------------------------------------------------- ValidDate Description Checks for the validity of a date and returns TRUE if valid. Syntax Function ValidDate( d : Date ) : Boolean ; ---------------------------------------------------------- FormatToDate Description Converts a formatted date to a Pascal date. Syntax Procedure FormatToDate( form: String;Var d : Date); Remarks Form is assumed to be a formatted date according to the current Date format set through SetDateFormat. See Also DateToFormat, FormatToField ---------------------------------------------------------- FieldToFormat Description Converts a Dbase Date format to Display Date format Syntax Function FieldToFormat( Fielddate : String) : String; Remarks Returned format is affected by Current format set through SetDateFormat. See Also FormatToField ---------------------------------------------------------- FormatToField Description Converts a Display Date Format to a Dbase Date Format. Syntax Function FormatToDate( Form : String ) : String; Remarks Form is a formatted Date String according to the current SetDateFormat. See Also FieldToFormat ---------------------------------------------------------- DaysFromZero ( Internal ) Description Returns the number of days from a certain date. Syntax Function DaysFromZero( d : Date ) : LongInt; Remarks This is the serial day from the given date. This is 1721119 days Less than the classical Julian Date. See Also Julian ---------------------------------------------------------- ********************************************************************** Unit DbStr.TPU ********************************************************************** Introduction String manipulations are done in this unit along with the three sound procedures: Beep, bleep and warnerror. ( Why wasting another unit for these? ) Ltrim, Rtrim and Trim are used to delete the trailing and leading spaces and Nulls. Upper converts a string to Uppercase. Thats it.. ********************************************************************** Beep Description Beeps a sound with the specified frequency Syntax Procedure Beep(Frequency : word); See Also Bleep, Warnerror ---------------------------------------------------------- Bleep Description Beeps twice with different frequency ( 1000, 2000 ) making a Bleep Syntax Procedure Bleep; See Also Warerror, Beep ---------------------------------------------------------- WarnError Description Bleeps if the argument is non zero. Syntax Procedure WarnError ( Error : byte ); Remarks Good to add with procedures that might have errors at anytime. See Also Beep , Bleep ---------------------------------------------------------- Fileexists Description Checks whether the specified file exist in the directory or not. Rturns TRUE if exists. Syntax Function Fileexists( Fname : String) : Boolean; Warning Does not Search for file in any path. ---------------------------------------------------------- Rtrim Description Trims the specified string from right. ( trailing ) and returns the trimmed string. Syntax Function Rtrim( s : String ) : String ; Remarks Spaces( 32 ) and Nulls ( 0 ) on the right are trimmed. Warning Ignores if string is NUL ( '' ). See Also Ltrim, Trim ---------------------------------------------------------- Ltrim Description Trims the leading spaces from the specified string and returns string. Syntax Function Ltrim ( s : String ) : string ; Remarks Spaces and nulls are trimmed. See Also Rtrim, Trim ---------------------------------------------------------- Trim Description Trims a string from Both side. Syntax Function Trim ( s : String ) : String ; Remarks This is the combination of bothe Ltrim and Rtrim. i.e. Trim (s) := Ltrim( Rtrim(s)) ; See Also Ltrim , Rtrim ---------------------------------------------------------- NumValid Description Checks whether a Numeric String is valid or not. If valid the value is returned in Re else Re is set to zero. Syntax Function NumValid( s : String; Var Re : Real ) : Boolean ; Remarks This is used to check the validity of the Numeric string in replace in Tbase. Warning Unlike in Pascal Val procedure, Spaces in Both sides are allowed here. Do NOT waste your code trimming before call. ---------------------------------------------------------- NumFormat Description Formats a real number with specified size and decimals and return string. Syntax Function NumFOrmat( re : Real; Len, Deci : Integer ):String; Remarks Used in Replace method to format numeric data in Tbase. Warning Only 11 digits of decimals are significant in Deci. See Also Cstr ---------------------------------------------------------- Cstr Description Formats a real number as in NumFormat and fills the spaces by '0'. Syntax Function Cstr( Re : Real; Len,Dec : Integer ) : String; Remarks Used to format Date string with leading zeros. eg. month = 03. ---------------------------------------------------------- Upper Description Converts the specified string to upper case. Syntax Function Upper ( s : string ) : String ; ---------------------------------------------------------- *********************************************************************** Unit DbWin.TPU *********************************************************************** Introduction Just some simple text windowing routines. Frankly, I am not interested in Text mode windowing. So any inconvenience is upto you. The routines are modifications of TP 6.0 examples Win.Pas and WinDemo.Pas. So, anyone asking the source code of all my units will not be given the codes of Dbwin. Sorry!.. Ask Borland. InitWindow initializes the windowing variables along with filling the screen with a block character. The colors are limitted in this desktop. Soory.. I am not that intersted to develop it more. I am doing somethign in Graphics now.. ************************************************************************ InitWindow Description Initializes the window variables and fill the screen with a block chracter making a DeskTop look. Syntax Procedure InitWindow( s : String ); Remarks String s is displayed on the top line of the screen as a heading. Use WriteHeader for a centered Heading. See Also WriteHeader, WriteFoot, OpenWindow ---------------------------------------------------------- OpenWindow Description Opens a window on the screen with Title and Foot. Syntax Procedure OpenWindow( x,y,x1,y1: Byte; Title, foot : String; Framecol, wincol : Word ); Remarks (x,y) ,(x1,y1) are the topleft and bottomright corners. Title is displayed in middle of top border.Foot is displayed on the right bottom. Framecol and wincol are colors to win. Warning Allowed values for (x,y) and (x1,y1) are (0,0) to (79,24) See Also CloseWindow ---------------------------------------------------------- CloseWindow Description Closes the recent window on the stack. Syntax Procedure CloseWindow; Remarks The topmost window is closed and its allocated memory is released. The next window becomes active with double line border. See Also OpenWIndow ---------------------------------------------------------- CursorOff Description Turns text the cursor OFF ( invisible ) Syntax Procedure CursorOff; See Also CursorOn ---------------------------------------------------------- CursorOn Description Turns the cursor ON ( Blinking ) Syntax Procedure CursorOn; See Also CursorOff ---------------------------------------------------------- WriteHeader Description Writes the heading in the Top line of the screen. Syntax Procedure WriteHeader( s : String ); Remarks Directly writes on the screen memory thus independent of any windows. Colors is taken from Crt ( TextAttr ) Text is centered. Warning If Length(s) is > 80, s is trimmed to fit. See Also WriteFoot ---------------------------------------------------------- WriteFoot Description Writes a foot note on the DeskTop. Syntax Procedure WriteFoot( s : String ); Remarks Window independent. Colors is taken from TextAttr. Text is Left adjusted. Add spaces to make alligned. Warning Trimmed to fit the line. See Also WriteHeader. ---------------------------------------------------------- DispWline Description Writes a string on the screen through direct memory access. Syntax Procedure DispWline( r, c, col : word ;var s : string ); Remarks Window Independant. ---------------------------------------------------------- Nasir Haniffa ( ACDH083@SAUPM00.BITNET )