面板中未触发默认按钮

Question

为什么当我在文本框中按回车时，lblMasterPhoneNumbers onclick 方法不触发？

       <asp:Panel ID="pnlSearch" DefaultButton="lbMasterPhoneNumber" runat="server">  
    <table cellpadding="0" cellspacing="0" border="0">
        <tr>
            <td>
                <asp:TextBox ID="txtSearchMaster" runat="server" CssClass="TextBoxSearchActive" EnableTheming="false" />    
            </td>
            <td>
                <%--<asp:Button ID="btnSearchMaster" CssClass="SearchButton" runat="server" OnClick="btnSearchMaster_Click" CausesValidation="false" EnableTheming="False" />--%>
            </td>
        </tr>
        <tr>
            <td colspan="2">
                <div style="margin-right:3px; color:white">                       
                    <asp:LinkButton ID="lbMasterPhoneNumber" runat="server" Text="Phone number" ForeColor="White" onclick="lbMasterPhoneNumber_Click" OnClientClick="javascript:ActivateLoadingIndicator()" /> &nbsp; | &nbsp;
                    <asp:LinkButton ID="lbMasterCDR" runat="server" Text="CDR" ForeColor="White" onclick="lbMasterCDR_Click" /> | &nbsp;
                    <asp:LinkButton ID="lbMasterSMS" runat="server" Text="SMS" ForeColor="White" onclick="lbMasterSMS_Click" />

                </div>
            </td>
        </tr>
    </table>
     </asp:Panel>

Answer 1

msdn 声明 defaultbutton 属性不支持链接按钮http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.panel.defaultbutton.aspx