Delphi DLL

Compress String Feed to Base64

See more Compression Examples

This example receives incoming text data in chunks, compresses as a stream, and accumulates the compressed data in base64. Delphi DLL

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
sbCompressedBase64: HCkStringBuilder;
compress: HCkCompression;
bdCompressed: HCkBinData;
sbUncompressedChunk: HCkStringBuilder;
i: Integer;
originalText: PWideChar;

begin
success := False;

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

sbCompressedBase64 := CkStringBuilder_Create();

compress := CkCompression_Create();
CkCompression_putAlgorithm(compress,'deflate');
CkCompression_putCharset(compress,'utf-8');
CkCompression_putEncodingMode(compress,'base64');

CkCompression_putFirstChunk(compress,True);
CkCompression_putLastChunk(compress,False);

bdCompressed := CkBinData_Create();
sbUncompressedChunk := CkStringBuilder_Create();

for i := 0 to 24 do
  begin
    if (i = 24) then
      begin
        CkCompression_putLastChunk(compress,True);
      end;

    CkStringBuilder_Clear(sbUncompressedChunk);
    CkStringBuilder_AppendInt(sbUncompressedChunk,i);
    CkStringBuilder_Append(sbUncompressedChunk,': This is a line of data to be compressed...' + #13#10);

    CkCompression_CompressSb(compress,sbUncompressedChunk,bdCompressed);

    CkCompression_putFirstChunk(compress,False);
  end;

Memo1.Lines.Add('The base64 encoded compressed text:');
Memo1.Lines.Add(CkBinData__getEncoded(bdCompressed,'base64'));

// Decompress in one call:
originalText := CkCompression__decompressStringENC(compress,CkBinData__getEncoded(bdCompressed,'base64'));
Memo1.Lines.Add(originalText);

CkStringBuilder_Dispose(sbCompressedBase64);
CkCompression_Dispose(compress);
CkBinData_Dispose(bdCompressed);
CkStringBuilder_Dispose(sbUncompressedChunk);

end;