private void DGUserEdit()

        {

            if(DGUser.SelectedItem!=null)

            {

                DataRow dr = (DGUser.SelectedItem as DataRowView).Row;

                Page.UserEdit UE = new UserEdit(UserGrade, dr["UserName"].ToString());//声明子窗体

                UE.Closed += new EventHandler(UE_Closed);//注册关闭事件

                UE.ShowDialog();

            }

        }

        //在子窗体的关闭里写要刷新的内容，我这是重写绑定

        private void UE_Closed(object sender,EventArgs e)

        {

            Band();

        }