Lazarus Pascal Requires Chilkat v11.0.0+

Extract a Single ZIP Entry While Preserving Its Stored Path

See more Zip Examples

This example demonstrates how to use the ZipEntry.Extract method to extract a single entry from a ZIP archive.

The example first creates a ZIP archive containing a text file. It then re-opens the ZIP, finds the entry, and extracts it to a base directory.

The Extract method uses the relative path stored within the ZIP entry. Any required subdirectories are created automatically beneath the specified base directory.

Lazarus Pascal

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.ZipEntry,
  Chilkat.Zip;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  zip: TZip;
  zip2: TZip;
  entry: TZipEntry;

begin
  success := False;

  //  ------------------------------------------------------------
  //  First create a sample ZIP archive containing a small text file.

  zip := TZip.Create;

  success := zip.NewZip('c:/temp/sampleText.zip');
  if (success = False) then
    begin
      WriteLn(zip.LastErrorText);
      Exit;
    end;

  //  Add a small text file from memory.
  success := zip.AddString('myApp/docs/hello.txt','Hello from a ZIP entry!','utf-8');
  if (success = False) then
    begin
      WriteLn(zip.LastErrorText);
      Exit;
    end;

  //  Write the ZIP archive to disk and close it.
  success := zip.WriteZipAndClose();
  if (success = False) then
    begin
      WriteLn(zip.LastErrorText);
      Exit;
    end;

  //  ------------------------------------------------------------
  //  Now open the ZIP archive we just created.

  zip2 := TZip.Create;

  success := zip2.OpenZip('c:/temp/sampleText.zip');
  if (success = False) then
    begin
      WriteLn(zip2.LastErrorText);
      Exit;
    end;

  //  Find the entry by its stored ZIP path.
  entry := TZipEntry.Create;

  success := zip2.EntryOf('myApp/docs/hello.txt',entry);

  if (success = False) then
    begin
      WriteLn('Entry not found.');
      Exit;
    end;

  //  Extract this single entry to the base directory:
  //  
  //      c:/temp/extracted
  //  
  //  Because the entry's stored path is:
  //  
  //      myApp/docs/hello.txt
  //  
  //  the file will be extracted to:
  //  
  //      qa_output/extracted/myApp/docs/hello.txt
  //  
  //  The required subdirectories are created automatically.
  success := entry.Extract('c:/temp/extracted');
  if (success = False) then
    begin
      WriteLn(entry.LastErrorText);
      Exit;
    end;

  zip2.CloseZip();

  WriteLn('Entry extracted successfully.');


  zip.Free;
  zip2.Free;
  entry.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.