string strsql = "select * from stu";
ada = new SqlDataAdapter(strsql, conn);
DataTable dt = new DataTable();
ada.Fill(dt, "stu");
            ada.Fill(dt);    如果 stu 是一张视图  BindingContext[dt].EndCurrentEdit();
            SqlCommandBuilder commandbuilder = new SqlCommandBuilder(this.ada);
            this.ada.Update(dt, "stu");
            dt.AcceptChanges();
            this.dataGridView1.Refresh();
可以生效吗?