Delphi DLL

Restart/Resume FTP Download

See more FTP Examples

Resume downloading a file from an FTP server. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Ftp2;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
ftp: HCkFtp2;
localFilename: PWideChar;
remoteFilename: PWideChar;

begin
success := False;

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

ftp := CkFtp2_Create();

CkFtp2_putHostname(ftp,'ftp.example.com');
CkFtp2_putUsername(ftp,'login');
CkFtp2_putPassword(ftp,'password');

// Connect and login to the FTP server.
success := CkFtp2_Connect(ftp);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkFtp2__lastErrorText(ftp));
    Exit;
  end;

// Change to the remote directory where the file is located.
// This step is only necessary if the file is not in the root directory
// for the FTP account.
success := CkFtp2_ChangeRemoteDir(ftp,'temp');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkFtp2__lastErrorText(ftp));
    Exit;
  end;

// To resume a download, it is assumed that the partial file
// is already present on the local filesystem.
// You only need to set the RestartNext property to resume
// the download.  The Chilkat FTP component sets the resume
// point by getting the existing size of the target (local) file.
CkFtp2_putRestartNext(ftp,True);

localFilename := 'big.zip';
remoteFilename := 'big.zip';

// Resume downloading...
success := CkFtp2_GetFile(ftp,remoteFilename,localFilename);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkFtp2__lastErrorText(ftp));
    Exit;
  end;

success := CkFtp2_Disconnect(ftp);

Memo1.Lines.Add('File Downloaded!');

CkFtp2_Dispose(ftp);

end;