Delphi ActiveX

Compress and Decompress a String

See more Compression Examples

Demonstrates how to compress and decompress a string. Delphi ActiveX

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;
sb: TChilkatStringBuilder;
i: Integer;
compress: TChilkatCompression;
compressedBytes: Array of Byte;
compressedBase64: WideString;
decompressedString: WideString;

begin
success := 0;

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

sb := TChilkatStringBuilder.Create(Self);

for i := 1 to 20 do
  begin
    sb.Append('This is the original uncompressed string.' + #13#10);
  end;

compress := TChilkatCompression.Create(Self);
compress.Algorithm := 'deflate';
// Indicate that the utf-8 byte representation of the string should be compressed.
compress.Charset := 'utf-8';

compressedBytes := compress.CompressString(sb.GetAsString());

// If the compressed data is desired in string format, then get the base64 representation of the bytes.
compress.EncodingMode := 'base64';
compressedBase64 := compress.CompressStringENC(sb.GetAsString());
Memo1.Lines.Add('Compressed Bytes as Base64: ' + compressedBase64);

// Now decompress...
decompressedString := compress.DecompressString(compressedBytes);
Memo1.Lines.Add('The original string after decompressing from binary compressed data:');
Memo1.Lines.Add(decompressedString);

// To decompress from Base64...
compress.EncodingMode := 'base64';
decompressedString := compress.DecompressStringENC(compressedBase64);
Memo1.Lines.Add('The original string after decompressing from Base64:');
Memo1.Lines.Add(decompressedString);
end;