Visual Studio 2010 Reporting Services错误消息子报表的数据检索失败

Question

在StackOverFlow：SSRS Subreport VS2010 data retrieval failed for the subreport中阅读此帖子之后，我仍然得到＆＃34;数据检索失败的子报告＆＃34;。主要报告和子报告在BIDS 2008中运行良好，因此我的.cs或.aspx页面必须出错。我使用的代码如下。谁能告诉我我做错了什么？谢谢！

aspx页面：

<asp:DropDownList ID="DropDownListVisit" runat="server" DataTextField="VisitList"
    DataValueField="VisitID" AutoPostBack="True"  AppendDataBoundItems="true"
    onselectedindexchanged="DropDownListVisit_SelectedIndexChanged"
    DataSourceID="EntityDataSourceVisitDropDown">
    <asp:ListItem Text="--- Select Ship & Visit ---" Value="" Selected="True"></asp:ListItem>
</asp:DropDownList>

<asp:EntityDataSource ID="EntityDataSourceVisitDropDown" runat="server"
    ConnectionString="name=Admiral_NSSAEntities"
    DefaultContainerName="Admiral_NSSAEntities" EnableFlattening="False"
    EntitySetName="vw_VisitList"
    Select="it.[VisitID], it.[VisitList], it.[ShipName], it.[StartDate]"
    OrderBy="it.[ShipName] asc, it.[StartDate] desc">
</asp:EntityDataSource>

<rsweb:ReportViewer ID="ReportViewerSummeryReportOutBrief" runat="server" Font-Names="Verdana"
    Font-Size="8pt" InteractiveDeviceInfos="(Collection)"
    WaitMessageFont-Names="Verdana" WaitMessageFont-Size="14pt" Width="1139px"
    Height="894px" PageCountMode="Actual" PromptAreaCollapsed="True"
    style="margin-right: 0px">
    <LocalReport ReportPath="Secured\Reports\SummeryReportOutBrief.rdlc">
        <DataSources>
            <rsweb:ReportDataSource DataSourceId="EntityDataSourceVisitInfo"
                Name="VisitInfo" />
            <rsweb:ReportDataSource DataSourceId="EntityDataSourceWorkOrders"
                Name="WorkOrders" />
            <rsweb:ReportDataSource DataSourceId="EntityDataSourcePartsDataByWorkOrder"
                Name="PartsDataByWorkOrder" />
        </DataSources>
    </LocalReport>
</rsweb:ReportViewer>

<asp:EntityDataSource ID="EntityDataSourcePartsDataByWorkOrder" runat="server"
    ConnectionString="name=Admiral_NSSAEntities"
    DefaultContainerName="Admiral_NSSAEntities" EnableFlattening="False"
    EntitySetName="vw_PartsDataByWorkOrder" >
</asp:EntityDataSource>

<asp:EntityDataSource ID="EntityDataSourceWorkOrders" runat="server"
    AutoGenerateOrderByClause="True" AutoGenerateWhereClause="True"
    ConnectionString="name=Admiral_NSSAEntities"
    DefaultContainerName="Admiral_NSSAEntities" EnableFlattening="False"
    EntitySetName="vw_WorkOrders" Where="">
    <WhereParameters>
        <asp:ControlParameter ControlID="DropDownListVisit" DbType="Guid"
            Name="VisitID" PropertyName="SelectedValue" />
    </WhereParameters>
</asp:EntityDataSource>

<asp:EntityDataSource ID="EntityDataSourceVisitInfo" runat="server"
    AutoGenerateOrderByClause="True" AutoGenerateWhereClause="True"
    ConnectionString="name=Admiral_NSSAEntities"
    DefaultContainerName="Admiral_NSSAEntities" EnableFlattening="False"
    EntitySetName="vw_VisitInfo" Where="">
    <WhereParameters>
        <asp:ControlParameter ControlID="DropDownListVisit" DbType="Guid"
            Name="VisitID" PropertyName="SelectedValue" />
    </WhereParameters>
</asp:EntityDataSource>

</asp:Content>

代码背后：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Microsoft.Reporting.WebForms;
using System.Configuration;

public partial class Secured_Reports_SummeryReportOutBriefAll : System.Web.UI.Page
{    
    protected void Page_Load(object sender, EventArgs e)
    {               
        if (DropDownListVisit.SelectedValue == "")
        {
            this.ReportViewerSummeryReportOutBrief.Visible = false;

            ReportViewerSummeryReportOutBrief.LocalReport.Refresh();             
            ReportViewerSummeryReportOutBrief.LocalReport.SubreportProcessing += new SubreportProcessingEventHandler(SubreportProcessingEventHandler);               
        }
    }

    public void SubreportProcessingEventHandler(object sender, SubreportProcessingEventArgs e)
    {

        e.DataSources.Add(new ReportDataSource("PartsDataByWorkOrder", this.EntityDataSourcePartsDataByWorkOrder));
    }

    protected void DropDownListVisit_SelectedIndexChanged(object sender, EventArgs e)
    {
        //In App_Code _TemplateFiles
        Reports.ShowReport(this.DropDownListVisit, this.ReportViewerSummeryReportOutBrief);
    }

}