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

        public static char[] GetInvalidFileNameChars() => new char[]
        { 
            '\"', '<', '>', '|', '\0', 
            (char)1, (char)2, (char)3, (char)4, (char)5, (char)6, (char)7, (char)8, (char)9, (char)10, 
            (char)11, (char)12, (char)13, (char)14, (char)15, (char)16, (char)17, (char)18, (char)19, (char)20, 
            (char)21, (char)22, (char)23, (char)24, (char)25, (char)26, (char)27, (char)28, (char)29, (char)30, 
            (char)31, ':', '*', '?', '\\', '/' 
        };

        private async void CreateFolder(string folderName)
        {
            if (string.IsNullOrWhiteSpace(folderName))
            {
                MessageBox.Show("Invalid folder name");
                return;
            }
            List <char> invalidChars = Path.GetInvalidFileNameChars().ToList();

            invalidChars.AddRange(Path.GetInvalidPathChars().ToList());
            foreach (char c in invalidChars)
            {
                if (folderName.Contains(c))
                {
                    MessageBox.Show(string.Format("value '{0}' is invalid for name", c));
                    return;
                }
            }
            CreatingFolderTextBlock.Visibility = Visibility.Visible;
            try
            {
                await Utils.FTPMakeFolderAsync(string.Format("{0}{1}", FTPPath, folderName), Credential);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
                return;
            }
            FTPReturnFolderName = folderName;
            FTPReturnPath       = string.Format("{0}{1}/", FTPPath, folderName);
            DialogResult        = true;
            Close();
        }