private void st_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e)
{
cancelClick = false;
if ((DateTime.Now.Ticks - clickTimer) < minClickTime && !settingValue)
{
cancelClick = true;
return;
}
if ((e.Node.FirstNode) == null)
editingControl.DropDown.Close(ToolStripDropDownCloseReason.ItemClicked);
}