dr["GradeId"] 这种结构是怎么实现的 他是数组吗?
string sql = "select GradeId ,GradeName from GradeInfo";
DataTable dtGradeList = SqlHelper.GetDataTable(sql);
DataRow dr = dtGradeList.NewRow();
dr["GradeId"] = 0;
dr["GradeName"] = "请选择";