(Delphi DLL) Append Files to Existing Zip w/out Rewriting Entire Zip

Demonstrates how to use the QuickAppend method to append files to an existing .zip archive. This method works by editing the existing .zip -- it does not rewrite or recompress the contents of the existing .zip. It is the fastest way to append additional files to a pre-existing large .zip archive. Note: The QuickAppend method is new and available in the pre-release downloads, or in official releases dated after 6-October-2007.

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

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
zip: HCkZip;
success: Boolean;
saveExtraPath: Boolean;

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

zip := CkZip_Create();

// The NewZip method only initializes the Zip object -- it does
// not create or write a .zip file.
success := CkZip_NewZip(zip,'notUsed.zip');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

// Add a reference to a file.  This is the file that will
// be added to a pre-existing .zip archive.  
// Note: this does not read or compress the file contents --
// it simply adds a reference to the zip object.
saveExtraPath := False;
success := CkZip_AppendOneFileOrDir(zip,'something.dat',saveExtraPath);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

// Appends the contents of the zip object to the preExisting.zip
// zip archive.  preExisting.zip is opened, and the files
// referenced by this zip object are streamed in, compressed,
// and appended to the end of the archive.
success := CkZip_QuickAppend(zip,'preExisting.zip');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkZip__lastErrorText(zip));
    Exit;
  end;

Memo1.Lines.Add('Success!');

// Note: Additional files, directory trees, or in-memory data
// can be appended by calling AppendOneFileOrDir, AppendFiles,
// AppendString, AppendData, etc. multiple times.
// Whatever files and/or in-memory data that are referenced by
// this zip object will be appended to preExisting.zip when
// QuickAppend is called

CkZip_Dispose(zip);

end;