Pascal (Lazarus/Delphi)

Compress Bytes

See more Compression Examples

Demonstrates how to compress binary data. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Compression,
  Chilkat.FileAccess;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  fac: TFileAccess;
  fileBytes: TBytes;
  compress: TCompression;
  compressedBytes: TBytes;

begin
  success := False;

  //  This example assumes the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  fac := TFileAccess.Create;

  fileBytes := fac.ReadEntireFile('qa_data/bmp/big.bmp');
  if (fac.LastMethodSuccess <> True) then
    begin
      WriteLn(fac.LastErrorText);
      Exit;
    end;

  compress := TCompression.Create;
  compress.Algorithm := 'deflate';

  compressedBytes := compress.CompressBytes(fileBytes);
  if (compress.LastMethodSuccess <> True) then
    begin
      WriteLn(compress.LastErrorText);
      Exit;
    end;

  success := fac.WriteEntireFile('qa_output/compressedBmp.dat',compressedBytes);
  if (fac.LastMethodSuccess <> True) then
    begin
      WriteLn(fac.LastErrorText);
      Exit;
    end;


  fac.Free;
  compress.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.