Dart

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. Dart

import 'package:chilkat/chilkat.dart';

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

  final ftp = CkFtp2();

  ftp.hostname = 'ftp.example.com';
  ftp.username = 'username';
  ftp.password = 'password';

  // Connect and login to the FTP server.
  try {
    ftp.connect();
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Set the current remote directory to where the file is located:
  try {
    ftp.changeRemoteDir('something');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // Test to see if the file exists by getting the file size by name. 
  // If a -1 is returned, the file does not exist.
  final fileSize = ftp.getSizeByName('test123.txt');
  if (fileSize < 0) {
    print('file does not exist');
  } else {
    print('file exists and is $fileSize bytes in size');
  }

  ftp.disconnect();
}