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

        public static string GetDirectoryName(string path)
        {
            if (path != null)
            {
                PathInternal.CheckInvalidPathChars(path);
                path = PathInternal.NormalizeDirectorySeparators(path);
                int root = PathInternal.GetRootLength(path);

                int i = path.Length;
                if (i > root)
                {
                    while (i > root && !PathInternal.IsDirectorySeparator(path[--i])) ;
                    return path.Substring(0, i);
                }
            }
            return null;
        }

    private void Search_OnClick(object sender, RoutedEventArgs e)
    {
        var ofd = new OpenFileDialog()
        {
            FileName         = "Select Folder.",
            InitialDirectory = PathTextBox.Text,
            ValidateNames    = false,
            CheckFileExists  = false,
            CheckPathExists  = false
        };

        if (ofd.ShowDialog(this) != true)
        {
            return;
        }
        PathTextBox !.Text = Path.GetDirectoryName(ofd.FileName) ?? "";
        PathTextBox.GetBindingExpression(TextBox.TextProperty)?.UpdateSource();
    }