internal void OnItemMiddleClick() {
if (ItemMiddleClick != null) {
var row = -1;
var column = -1;
this.HitTest(this.PointToClient(Cursor.Position), out row, out column);
if (row != -1 && this.Items[row].IsFolder)
ItemMiddleClick.Invoke(this, new NavigatedEventArgs(this.Items[row], this.Items[row]));
}
}