Chip 2000 February/Chip_2000-02_cd.bin/zkuste/Delphi/navody/tip2/505.txt

Text File | 1999-11-15 | 4KB | 111 lines

{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}
{ Downloaded from The Coder's Knowledge Base                         }
{ http://www.netalive.org/ckb/                                       }
{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}
{ @ CKB Header Version.: 1.01                                        }
{ @ Category ID........: delphi_misc                                 }
{ @ Added to database..: 14.10.98                                    }
{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}
{ @ Title..............: Data in executable                          }
{ @ Original Filename..: DataInExe.txt                               }
{ @ Author.............: Peter Below                                 }
{ @ Description........: How to include and retrieve data in/from exe }
{ @ Tested w. Compiler.: not tested yet                              }
{ @ Submitted by.......: Mike Orriss ([e-mail])                }
{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}


You can include any kind of data as a RCDATA or user type resource. This is very simple. The following is from a message on a related item  and should show you the general technique.

 Type
   TStrItem = String[39];  { 39 characters + length byte -> 40 bytes }
   TDataArray= Array [0..7, 0..24] of TStrItem;

 Const
   Data : TDataArray = (
     ('..', ...., '..' ),  { 25 strings per row }
     ...                   { 8 of these rows }
     ('..', ...., '..' )); { 25 strings per row }

The data will end up in your data segment and consume 8K of it. If that is too much for you, put the actual data into a RCDATA resource.  For that you proceed like this. Write a small windowless program that declares the typed constant as above and does nothing more than  write it to a disk file:

 Program MakeData;
 Type
   TStrItem = String[39];  { 39 characters 0 length byte -> 40 bytes }
   TDataArray= Array [0..7, 0..24] of TStrItem;

 Const
   Data : TDataArray = (
     ('..', ...., '..' ),  { 25 strings per row }
     ...                   { 8 of these rows }
     ('..', ...., '..' )); { 25 strings per row }

 Var
   F: File of TDataArray;
 Begin
   Assign( F, 'data.dat' );
   Rewrite(F);
   Write(F, Data);
   Close(F);
 End.

Now prepare a resource file, lets call it DATA.RC. It contains only the following line:

 DATAARRAY RCDATA "data.dat"

Save it, open a DOS box, change to the directory you saved data.rc to (same as data.dat is in!), run the following command:

 brcc data.rc   (brcc32 for Delphi 2.0)

That gives you a data.res file you can now include in your Delphi project. At runtime you can now generate a pointer to that resource data  and access it as needed.


 { in a Unit interface section  }
 Type
   TStrItem = String[39];  { 39 characters + length byte -> 40 bytes }
   TDataArray= Array [0..7, 0..24] of TStrItem;
   PDataArray= ^TDataArray;
 Const
   pData: PDataArray = Nil;   { use a Var in Delphi 2.0}

 Implementation
 {$R DATA.RES}

 Procedure LoadDataResource;
 Var
   dHandle: THandle;
 Begin
   { pData := Nil; if pData is a Var }
   dHandle := FindResource( hInstance, 'DATAARRAY' , RT_RCDATA );
   If dHandle <> 0 Then Begin
     dhandle := LoadResource( hInstance, dHandle );
     If dHandle <> 0 Then
       pData := LockResource( dHandle );
   End;
   If pData = Nil Then
     { failed, issue appropriate error message, use WinProcs.MessageBox,
       not VCL stuff, since the code here will execute as part of the
       program startup sequence and VCL may not have initialized yet! }
 End;

 Initialization
   LoadDataResource;
 End.

Now you can refer to items in the array with pData^[i,j]-syntax.

 - Peter Below