Asp.net Telerik Radgrid-Eval语句仅返回列表中的第一项

我已经使用一个项目模板创建了一个html表，这样我就可以格式化pdf导出。我遇到的问题是，我正在从数据库返回多个元素，但是Eval语句将只显示第一个元素。我已经尝试创建一个嵌套的radgrid，但是设计师不会拾取项目模板中的telerik控件。下面显示的类列表将只返回一个类

<telerik:RadGrid RenderMode="Lightweight" ID="RadGridWrapper1" runat="server" OnItemCommand="radGridLoanOnboarding_ItemCommand" 
    OnNeedDataSource="RadGridWrapper1_NeedDataSource" GroupingEnabled="true" AllowPaging="true" >
    <ExportSettings OpenInNewWindow="true" ExportOnlyData="false" Pdf-BorderType="NoBorder" >
        <Pdf DefaultFontFamily="Arial Unicode MS" AllowPrinting="true" ForceTextWrap="true" BorderType="NoBorder" >
            <PageHeader>
                <LeftCell TextAlign="Center" />
                <MiddleCell TextAlign="Center" Text="My Class List" />
                <RightCell Text="Page: <?page-number?>" TextAlign="Center" />
            </PageHeader>
        </Pdf>
    </ExportSettings>
    <MasterTableView AutoGenerateColumns="false" ShowHeader="false" CommandItemDisplay="top" TableLayout="Auto" >
        <CommandItemTemplate>
            <div class="container-fluid m-3">
                <asp:LinkButton ID="btnExport" CommandName="ExportToPdf" runat="server" CssClass="mr-3 float-right" ToolTip="Export to PDF">
                    <i class="fas fa-3x fa-file-pdf"></i>
                </asp:LinkButton>
            </div>
        </CommandItemTemplate>
        <CommandItemSettings ShowExportToCsvButton="false" ShowExportToExcelButton="false" ShowExportToPdfButton="true"
            ShowExportToWordButton="false" ShowAddNewRecordButton="false" />
                <Columns>
                    <telerik:GridTemplateColumn UniqueName="ClassListDisplay">
                        <ItemTemplate>
                            <table style="width: 100%; text-align: left">
                                <colgroup>
                                    <col />
                                </colgroup>
                                <tr style="border:none">
                                    <td>&nbsp;</td>
                                </tr>
                                <tr style="font-size: 14pt; margin-top: 5px; padding-top:5px; vertical-align: middle; text-align: left; border-top: 2px solid; background-color: lightgray;"
                                    class="greyHeader">
                                    <td>
                                        <i>INFO...</i>
                                    </td>
                                    <td></td>
                                </tr>
                                <tr style="border:none">
                                    <td>&nbsp;</td>
                                </tr>
                                <tr>
                                    <td><b>Classes</b>: <%# Eval("ClassList") %></td>
                                </tr>
                            </table>
                        </ItemTemplate>
                    </telerik:GridTemplateColumn>
                </Columns>
    </MasterTableView>
</telerik:RadGrid>