SAP Crystal Reports for VS2010数据绑定，过滤不适用

Question

我正在使用以下代码在页面加载事件中绑定Crystal Reports。

 using (MilitrymessEntities entity = new MilitrymessEntities())
            {

                BarporderReports barporpt = new BarporderReports();

                barporpt.Refresh();


                barporpt.SetDataSource(query);

                //barporpt.SetParameterValue("norows", 10);
                crviewer_barpurchaseorder.RefreshReport();

                crviewer_barpurchaseorder.ReportSource = barporpt;
            }

正确绑定并显示报告。我在按钮单击事件中将过滤器应用于报表，当我单击搜索按钮时，报表显示的是同一组数据。它没有显示过滤后的值。按钮单击事件代码如下：

 using (MilitrymessEntities entity = new MilitrymessEntities())
        {

            DateTime dt1 = Convert.ToDateTime(txt_fromdate.Text);
            DateTime dt2 = Convert.ToDateTime(txt_todate.Text);

            string strdt1 = dt1.Date.ToString("MM/dd/yyyy");
            string strdt2 = dt2.Date.ToString("MM/dd/yyyy");

            dt1 = Convert.ToDateTime(strdt1);
            dt2 = Convert.ToDateTime(strdt2);


                           var query = from data in entity.BarPurchaseOrders.AsEnumerable()
                         where  (data.Date >= dt1) && (data.Date <= dt2) && data.ItemName == drp_itemname.SelectedItem.Text
                        select data;


                           BarporderReports barporpt = new BarporderReports();
                           barporpt.Refresh();

                           barporpt.SetDataSource(query);


             crviewer_barpurchaseorder.RefreshReport();
            crviewer_barpurchaseorder.ReportSource = barporpt;




        }

你对这个问题有什么看法吗？

Answer 1

您需要检查页面加载事件的帖子。如下所示，

if(!page.IsPostback())
{
   using (MilitrymessEntities entity = new MilitrymessEntities())
   {
      BarporderReports barporpt = new BarporderReports();
      barporpt.Refresh();
      barporpt.SetDataSource(query);
      crviewer_barpurchaseorder.RefreshReport();
      crviewer_barpurchaseorder.ReportSource = barporpt;
   }
}

此外，您应该在刷新之前设置报告和数据源，

BarporderReports barporpt = new BarporderReports();
barporpt.SetDataSource(query);
barporpt.Refresh();

crviewer_barpurchaseorder.ReportSource = barporpt;
crviewer_barpurchaseorder.RefreshReport();