private void ButtonAdd_Click(object sender, RoutedEventArgs e)
 {
     using (var dialog = new WinForms.FolderBrowserDialog())
     {
         WinForms.DialogResult result = dialog.ShowDialog();
         if (result == WinForms.DialogResult.OK)
         {
             BackupDirectories.Add(dialog.SelectedPath);
         }
     }
 }
        /// <summary>
        /// Reads a text file encoded like below:
        /// 1:path
        /// 2:username
        /// 3:password
        /// 4:local-path
        /// 4: ...
        /// 4: local-path
        /// 5: excluded-path
        /// 5: ...
        /// </summary>
        /// <param name="file"></param>
        private void ReadSettings(String file)
        {
            BackupDirectories.Clear();
            if (!File.Exists(file))
            {
                return;
            }
            String line = String.Empty;

            using (StreamReader sr = new StreamReader(file))
            {
                while ((line = sr.ReadLine()) != null && !String.IsNullOrEmpty(line.Trim()))
                {
                    if (line.StartsWith("1:"))
                    {
                        TextBoxPath.Text = line.Substring(2);
                    }
                    else if (line.StartsWith("2:"))
                    {
                        TextBoxUsername.Text = line.Substring(2);
                    }
                    else if (line.StartsWith("3:"))
                    {
                        TextBoxPassword.Text = line.Substring(2);
                    }
                    else if (line.StartsWith("4:"))
                    {
                        BackupDirectories.Add(line.Substring(2));
                    }
                    else if (line.StartsWith("5:"))
                    {
                        ExcludedDirectories.Add(line.Substring(2));
                    }
                    else
                    {
                        throw new Exception(line);
                    }
                }
                sr.Close();
            }
        }