(Delphi ActiveX) GZip Create / Extract .gz File

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.

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
gzip: TChilkatGzip;
success: Integer;
xmlStr: WideString;

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

gzip := TChilkatGzip.Create(Self);

// File-to-file GZip:
// Compress "hamlet.xml" to create "hamlet.xml.gz"
success := gzip.CompressFile('hamlet.xml','hamlet.xml.gz');
if (success <> 1) then
  begin
    Memo1.Lines.Add(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 <> 1) then
  begin
    Memo1.Lines.Add(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 <> 1) then
  begin
    Memo1.Lines.Add(gzip.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add(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
end;