Pascal (Lazarus/Delphi)

GZip Create / Extract .gz File

See more Gzip Examples

Demonstrates how to compress a file to create a .gz (GZip) file.

Note: The .gz file format is a compressed file format. It contains a single file. The .gz file format is not an archive format (i.e. it does not contain a collection of files/directories such as with the .zip, .rar, or .tar file formats). GZip is often combined with TAR to create a .tgz (or .tar.gz).

Note: It is possible for a .gz to contain more than one file, but this is very uncommon.

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.Gzip;

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

procedure RunDemo;
var
  success: Boolean;
  gzip: TGzip;
  xmlStr: string;

begin
  success := False;

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

  gzip := TGzip.Create;

  //  File-to-file GZip:
  //  Compress "hamlet.xml" to create "hamlet.xml.gz";
  success := gzip.CompressFile('hamlet.xml','hamlet.xml.gz');
  if (success = False) then
    begin
      WriteLn(gzip.LastErrorText);
      Exit;
    end;

  //  File-to-file ungzip
  //  Decompress "hamlet.xml.gz" to create "hamletOut.xml";
  success := gzip.UncompressFile('hamlet.xml.gz','hamletOut.xml');
  if (success = False) then
    begin
      WriteLn(gzip.LastErrorText);
      Exit;
    end;

  //  File-to-string ungzip
  //  Decompress the contents of a .gz directly to a string variable:
  //  The 2nd argument indicates the charset of the character
  //  data after it is decompressed.

  xmlStr := gzip.UncompressFileToString('hamlet.xml.gz','utf-8');
  if (success = False) then
    begin
      WriteLn(gzip.LastErrorText);
      Exit;
    end;

  WriteLn(xmlStr);

  //  The Chilkat GZip API provides much more flexibility than shown
  //  here.  See the reference documentation at 
  //  http://www.chilkatsoft.com/refdoc for more information.


  gzip.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.