SqlConnection sqlcon;
                string sqlstr = @"SELECT OrderDetails.ProductID  AS  产品编码,
                                Product.ProdName AS 产品名称 ,
                                Product.Unit AS 单位 ,
                                OrderDetails.Price AS 单价,
                                OrderDetails.QTY AS 数量,
                                OrderDetails.QTY*OrderDetails.Price AS 总金额,
                                From OrderDetails left join Product on OrderDetails.ProductID=product.productid Order BY ProductID ";

                this.SqlDataSourceDetails.SelectCommand = sqlstr;
                this.SqlDataSourceDetails.DataBind();
                sqlcon = new SqlConnection(connectionString);
                SqlDataAdapter da = new SqlDataAdapter(sqlstr, sqlcon);
                DataSet ds = new DataSet();
                sqlcon.Open();
                da.Fill(ds, "OrderDetails");
                GridView1.DataSourceID = "";
                GridView1.DataSource = ds;
                GridView1.DataBind();