我很久沒用ADO.NET操作數據了，現在有個WinForm項目需要用到，知識都忘完了。以下是我寫的更新，大家看看缺少點什么嗎？我點擊更新的時候數據顯示更新，但是不更新數據庫。int num = 0;            for (int i = 0; i < this.dataGridView1.SelectedRows.Count;i++ )            {                int id = Convert.ToInt32(this.dataGridView1.SelectedRows[i].Cells[i].Value.ToString());                //MessageBox.Show(id+"show");                OleDbConnection conn = Dbconnection.Getcon();                conn.Open();                OleDbCommand command = new OleDbCommand("update Users set UserState='1' where UserID=" + id.ToString(), conn);                num = command.ExecuteNonQuery();                               conn.Close();            }                           MessageBox.Show("刪除成功");                dataBind();