(Delphi ActiveX) Decompress Gzip Data In-Place Using BinData

See more Gzip Examples

This example demonstrates how to use the UncompressBd method to decompress Gzip data stored in a BinData object.

The compressed .gz file is first loaded into memory. The UncompressBd method then decompresses the data in-place, meaning the original compressed bytes in the BinData object are replaced with the uncompressed data.

After decompression, the example writes the resulting data to a file. This approach is useful when working entirely in memory before saving or further processing the uncompressed data.

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
success: Integer;
gzip: TChilkatGzip;
bd: TChilkatBinData;

begin
success := 0;

// This example demonstrates how to decompress Gzip data stored in a BinData object.
// The decompression is done in-place, replacing the compressed data with the original data.

gzip := TChilkatGzip.Create(Self);
bd := TChilkatBinData.Create(Self);

// Load a .gz file into BinData:
success := bd.LoadFile('example.txt.gz');
if (success = 0) then
  begin
    Memo1.Lines.Add(bd.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('Compressed size (bytes): ' + IntToStr(bd.NumBytes));

// Uncompress the data in-place:
success := gzip.UncompressBd(bd.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(gzip.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('Decompressed size (bytes): ' + IntToStr(bd.NumBytes));

// Save the uncompressed data to a file:
success := bd.WriteFile('example.txt');
if (success = 0) then
  begin
    Memo1.Lines.Add(bd.LastErrorText);
    Exit;
  end;

Memo1.Lines.Add('File successfully uncompressed to example.txt');
end;