this._dataset = new DataSet();                    this._sdap.Fill(this._dataset, "學(xué)生表");                    this._sdap.FillSchema(this._dataset.Tables[0], SchemaType.Mapped);                    this._dr = this._dataset.Tables[0].Rows.Find(this._intid);                    this._dr["姓名"] = txt姓名.Text.Trim();                    this._dr["年齡"] = int.Parse(txt年齡.Text.Trim());                    this._dr["班級(jí)"] = int.Parse(cbb班級(jí).SelectedValue.ToString());                    this._dataset.Tables["學(xué)生表"].Rows.Remove(this._dr);　　　　　　 return this._sdap.Update(this._dataset, "學(xué)生表") > 0 ? true : false;為什么dataset中的信息刪除掉了  卻在更新數(shù)據(jù)庫(kù)的時(shí)候出錯(cuò)了 ？為什么？  哪位高手指點(diǎn)下??！