Question

我收到了这个错误！当打开水晶报告follong代码。

数据源对象无效。

代码在这里

Cursor = Cursors.WaitCursor;
            timer1.Enabled = true;
            CrystalReport2 rpt = new CrystalReport2();
            obj.connection();
            String accept = "SELECT S.Product as Products, COALESCE(Pur_Orders.Quantity, 0) as [Products purchased], COALESCE(Sale_Orders.Quantity, 0) as [Products Sold] From Inv_stock S LEFT JOIN (SELECT Item, SUM(Quantity) AS Quantity FROM Pur_Orders Where Pur_Orders.Date='" + dateTimePicker1.Value.Date + "' GROUP BY Item) AS Pur_Orders ON S.Product = Pur_Orders.Item LEFT JOIN (SELECT Item, SUM(Quantity) AS Quantity FROM Sale_Orders Where Sale_Orders.Date='" + dateTimePicker1.Value.Date + "' GROUP BY Item) AS Sale_Orders ON S.Product = Sale_Orders.Item";
            SqlCommand cmd = new SqlCommand(accept, obj.con);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataSet ds = new DataSet();
            da.Fill(ds, "Inv_stock");
            da.Fill(ds, "Pur_Orders");
            da.Fill(ds, "Sale_Orders");
            rpt.SetDataSource(da);
            obj.con.Close();
            Inventory inv = new Inventory();
            inv.CrystalReportViewer.ReportSource = rpt;
            inv.Visible = true;

什么是问题?????

Answer 1

您正在使用DataAdapter设置报告的数据源：

rpt.SetDataSource（DA）;

将其替换为数据集或数据表，如下所示：

rpt.SetDataSource（DS）; //数据集

rpt.SetDataSource（ds.Tables [ “表名”]）; //数据表

Answer 2

您应该创建嵌套查询的视图并检查它，然后在您将新报表作为数据时调用该特定视图。如果您的查询是正确的但数据课程无效，您将无法在报告中获得所需的输出..

数据源对象无效

2 个答案: