System.IO.Path.GetExtension C# (CSharp) Méthode

        public static string GetExtension(string path)
        {
            if (path == null)
                return null;

            PathInternal.CheckInvalidPathChars(path);
            int length = path.Length;
            for (int i = length - 1; i >= 0; i--)
            {
                char ch = path[i];
                if (ch == '.')
                {
                    if (i != length - 1)
                        return path.Substring(i, length - i);
                    else
                        return string.Empty;
                }
                if (PathInternal.IsDirectoryOrVolumeSeparator(ch))
                    break;
            }
            return string.Empty;
        }

        public void Load()
        {
            var dialog = new FolderBrowserDialog();

            dialog.ShowNewFolderButton = false;
            var    res           = dialog.ShowDialog();
            string directoryName = null;

            if (res == System.Windows.Forms.DialogResult.OK)
            {
                directoryName = dialog.SelectedPath;
            }
            if (directoryName == null)
            {
                return;
            }
            var    filesName   = new List <string>(Directory.GetFiles(directoryName));
            string inkFileName = null;

            foreach (var fileName in filesName)
            {
                if (!fileName.Contains("_ink.xaml") || !Path.GetExtension(fileName).Equals(".xaml"))
                {
                    continue;
                }
                inkFileName = fileName;
                break;
            }
            if (inkFileName == null)
            {
                return;
            }
            LoadInkCanvas(inkFileName, filesName);
            LoadChild(filesName);
        }