File Existence Check

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.

Download Chilkat FTP2 ActiveX

uses
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
    Dialogs, StdCtrls,
    CHILKATFTP2Lib_TLB,
    OleCtrls;

...

procedure TForm1.Button1Click(Sender: TObject);
var
ftp: TChilkatFtp2;
success: Integer;
fileSize: Integer;

begin
ftp := TChilkatFtp2.Create(Self);

//  Any string unlocks the component for the 1st 30-days.
success := ftp.UnlockComponent('Anything for 30-day trial');
if (success <> 1) then
  begin
    ShowMessage(ftp.LastErrorText);

  end;

ftp.Hostname := 'ftp.***.com';
ftp.Username := '***';
ftp.Password := '***';

//  Connect and login to the FTP server.
success := ftp.Connect();
if (success <> 1) then
  begin
    ShowMessage(ftp.LastErrorText);

  end;

//  Set the current remote directory to where the file is located:
success := ftp.ChangeRemoteDir('/something');
if (success <> 1) then
  begin
    ShowMessage(ftp.LastErrorText);

  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 := ftp.GetSizeByName('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;

ftp.Disconnect();
end;