DropDownList例子

ds = new DataSet();
            ds = GetNowSchool();
            if (ds.Tables[0].Rows.Count != 0)
            {
                drpNowSchool.DataSource = ds.Tables[0].DefaultView;
                drpNowSchool.DataTextField = "SchoolName";
                drpNowSchool.DataValueField = "SchoolID";
                drpNowSchool.DataBind();
            }
            drpNowSchool.Items.Insert(0, "--选择所属学校--");
            drpNowSchool.Items[0].Value = Convert.ToString(0);

选择的ID:drpNowSchool.selectedvalue