Question

我有一个显示报告的CrystalReportViewer。我正在向它传递两个参数来改变数据。这是有效的，除非您尝试进一步深入查看报告，此时它将重置为默认参数。

这有点像reportviewer元素刷新自己并忘记一切。我确实有一个page_init方法试图将值推回去，但是我得到了对象引用错误，所以可能做错了。

我还应该尝试什么？请参阅以下代码：

 protected void Page_Load(object sender, EventArgs e)
    {
        if (Session["ReportSource"] != null)
        {
            CrystalReportViewer1.ReportSource = (ReportDocument)Session["ReportSource"];
        }
        else
        {
            ReportDocument reportDocument = new ReportDocument();
            reportDocument.Load(Server.MapPath("~/Report/In Out.rpt"));
            reportDocument.SetDatabaseLogon("user", "pass" ,@"server", "db"); //removed credentials for stackoverflow!
            CrystalReportViewer1.ReportSource = reportDocument;
            Session["ReportSource"] = reportDocument;

        }
    }

    protected void butReport_Click(object sender, EventArgs e)
    {
        ReportDocument reportDocument = new ReportDocument();
        reportDocument.Load(Server.MapPath("./Report/In Out.rpt"));
          reportDocument.SetDatabaseLogon("user", "pass" ,@"server", "db"); //removed credentials for stackoverflow!    
        ///Load Session variables with values from web-controls
        Session["@FromDate"] = ConvertToDateTime(Request.Form["StartDate"]);
        Session["@ToDate"] = ConvertToDateTime(Request.Form["EndDate"]);
        reportDocument.SetParameterValue("Start", Session["@FromDate"]);
        reportDocument.SetParameterValue("End", Session["@ToDate"]);
        CrystalReportViewer1.ReportSource = reportDocument;
    }

我的CR嵌入如下

<div align="center">
            <asp:TextBox ID="StartDate" runat="server" type="date" placeholder="e.g. 31/12/2014" ></asp:TextBox> 
            <asp:TextBox ID="EndDate" runat="server" type="date" placeholder="e.g. 31/12/2014" ></asp:TextBox>
            <asp:button runat="server" id="Submit" type="button" value="Show Report" Text="View Report" onclick="butReport_Click" /></div>

        <div>
<CR:CrystalReportViewer ID="CrystalReportViewer1" runat="server" 
                   AutoDataBind="True" EnableDatabaseLogonPrompt="False" 
                   GroupTreeImagesFolderUrl="" Height="940px" 
                   ToolbarImagesFolderUrl="" ToolPanelWidth="200px" Width="1411px" 
                   EnableParameterPrompt="False" ReuseParameterValuesOnRefresh="True" 
                   ReportSourceID="CrystalReportSource1" />
               <CR:CrystalReportSource ID="CrystalReportSource1" runat="server">
                   <Report FileName="Report\In Out.rpt">
                   </Report>
               </CR:CrystalReportSource>
</div>

Answer 1

如果要在会话中保存加载的Crystal Reports文档，则应在初始化参数后执行此操作。目前发生奇怪的刷新事情已经太晚了，你在页面init中重新加载它的代码显然并不包含该参数加载代码。

public class GameFragment extends Fragment implements GameView {
    private GamePresenter presenter;

    @Override
    public void onCreate(Bundle savedInstanceState){
        presenter = new GamePresenter(this);
    }
}

另一种选择是简单地将protected void Page_Load(object sender, EventArgs e) { if (Session["ReportSource"] != null) CrystalReportViewer1.ReportSource = (ReportDocument)Session["ReportSource"]; } protected void butReport_Click(object sender, EventArgs e) { ReportDocument reportDocument = new ReportDocument(); /* your code to load the document and assign it as datasource to the CrystalReportViewer */ // Assign your result to the session: Session["ReportSource"] = reportDocument; }中的所有内容拆分为一个新函数，并从按钮单击和初始化调用它：

butReport_Click

注意，我不确定ASP.NET中这些对象的资源管理方式如何;我知道在我的Windows应用程序中（将它们转换为PDF）我不得不非常小心地关闭文档以避免错误，因此第一种方法在这方面可能更可取，因为它只打开文档一次并保留对象

此外，嵌入式asp xml是否已经在页面加载时加载文档，再次没有这些必需的参数？

CrystalReportViewer遗忘参数

1 个答案: