Delphi DLL

File Existence Check

See more FTP Examples

Testing to see if a file exists on the FTP server. The GetSizeByName method is a convenient way to check if a file exists. It will return -1 if the file does not exist, otherwise it returns the size of the file in bytes. 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;
fileSize: Integer;

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,'username');
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;

// Set the current remote directory to where the file is located:
success := CkFtp2_ChangeRemoteDir(ftp,'something');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkFtp2__lastErrorText(ftp));
    Exit;
  end;

// Test to see if the file exists by getting the file size by name. 
// If a -1 is returned, the file does not exist.
fileSize := CkFtp2_GetSizeByName(ftp,'test123.txt');
if (fileSize < 0) then
  begin
    Memo1.Lines.Add('file does not exist');
  end
else
  begin
    Memo1.Lines.Add('file exists and is ' + IntToStr(fileSize) + ' bytes in size');
  end;

success := CkFtp2_Disconnect(ftp);

CkFtp2_Dispose(ftp);

end;