DataGridItem t = e.Item;
   string ItemName = ((TextBox)t.FindControl("TextBox4")).Text;
   string TypeName =((DropDownList)t.FindControl("DropDownList3")).SelectedValue.ToString();
   string SZName =((DropDownList)t.FindControl("DropDownList4")).SelectedValue.ToString();
   string ShowName = ((TextBox)t.FindControl("TextBox5")).Text;
   string sql = "update  TrafficTable set TrafficItemName='" + ItemName + "',TrafficeType='" + TypeName + "',TrafficeFixation='" + SZName + "',TrafficeExplain='" + ShowName + "' where TrafficID=" + ();

你自己运行一下不就知道了!!!

应该没错

建议楼主把sql语句放到数据库里试试
你写到这里谁也看不出来的