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Delphi DLL

Restart/Resume FTP Upload

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Demonstrates how to restart / resume an FTP upload.

Chilkat Delphi DLL Downloads

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 will be uploaded.
success := CkFtp2_ChangeRemoteDir(ftp,'temp');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkFtp2__lastErrorText(ftp));
    Exit;
  end;

// In this example, assume that a previous FTP upload failed,
// and the incomplete file (bigFile.zip) exists on the FTP server.
// You only need to set the RestartNext property to resume
// the upload.  When RestartNext is set, the next call
// to PutFile (or PutFileFromBinaryData, PutFileFromTextData)
// will automatically resume the upload from the point of failure.
// (The way it works is that the FTP component sends a "SIZE"
// command to the FTP server to find out how many bytes of
// the file already exist on the server.  It then begins
// uploading from that point.

// Note: After PutFile is called, the RestartNext property
// is automatically set to false.
CkFtp2_putRestartNext(ftp,True);

// Upload a file with restart.
localFilename := 'bigFile.zip';
remoteFilename := 'bigFile.zip';

success := CkFtp2_PutFile(ftp,localFilename,remoteFilename);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkFtp2__lastErrorText(ftp));
    Exit;
  end;

success := CkFtp2_Disconnect(ftp);

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

CkFtp2_Dispose(ftp);

end;