在GridView的BottomPagerRow中找不到控件

我有一个非常简单的应用程序，它有一个GridView。我有一个自定义的BottomPagerRow，它使用了下拉列表和链接按钮。如果我试图在默认页面显示时使用控件，它可以正常工作，但如果我更改页面大小，任何其他更改都会迫使它返回默认值。

我自己看看这段代码，我只能认为，因为行号在改变，控件的ID也在改变，当服务器试图找到它们时，它们就不存在了，并切换到默认值。

<asp:GridView ID="dgCQMain" runat="server" EnableViewState="false" PagerSettings-Position="Bottom" OnPageIndexChanging="dgCQMain_PageIndexChanging" AutoGenerateColumns="true" OnRowCreated="dgCQMain_RowCreated">
    <HeaderStyle CssClass="gridHeaderRow" />
    <AlternatingRowStyle CssClass="gridAlternatingRows" />
    <PagerStyle CssClass="gridPager" />
    <RowStyle CssClass="gridRow" />
    <SelectedRowStyle CssClass="gridSelectedRow" />
    <FooterStyle CssClass="gridFooter" />
    <EmptyDataTemplate>
       <asp:Label ID="lblEmptyLaboratoryMain" runat="server" Text="[There are no current items for this patient]"></asp:Label>
       </EmptyDataTemplate>
       <EmptyDataRowStyle CssClass="gridEmpty" />
       <PagerTemplate>
          <table width="100%" cellpadding="0" cellspacing="0" border="0">
             <tr class="gridPager">
                <td class="pagerNumbers">
                   <asp:LinkButton CssClass="pagerNumberLinks" ID="LinkButton1" runat="server" CommandName="Page" CausesValidation="false" CommandArgument="First"><<</asp:LinkButton>
                   |
                   <asp:LinkButton CssClass="pagerNumberLinks" ID="LinkButton2" runat="server" CommandName="Page" CausesValidation="false" CommandArgument="Prev"><</asp:LinkButton>
                   |
                   <asp:Repeater ID="rptPager" runat="server">
                      <ItemTemplate>
                         <asp:LinkButton CssClass="pagerNumberLinks" ID="lnkPage" runat="server" Text='<%#Eval("Text") %>' CommandArgument='<%#Eval("Value") %>' Enabled='<%# Eval("Enabled") %>' OnClick="dgCQMainPage_Changed"></asp:LinkButton>
                         <span>|</span>
                       </ItemTemplate>
                    </asp:Repeater>
                 <asp:LinkButton CssClass="pagerNumberLinks" ID="LinkButton4" runat="server" CommandName="Page" CausesValidation="false" CommandArgument="Next">></asp:LinkButton>
                 |
                 <asp:LinkButton CssClass="pagerNumberLinks" ID="LinkButton5" runat="server" CommandName="Page" CausesValidation="false" CommandArgument="Last">>></asp:LinkButton>
                 |
               </td>
               <td class="gridPager">
                  <asp:Label ID="MessageLabel" Text="Show me" runat="server" />
                  <asp:DropDownList ID="PageDropDownList" AutoPostBack="true" runat="server" OnSelectedIndexChanged="dgCQMainDropDownList_SelectedIndexChanged_Bottom">
                     <asp:ListItem Text="2" />
                     <asp:ListItem Text="5" />
                     <asp:ListItem Text="10" />
                  </asp:DropDownList>
                  <asp:Label ID="Label1" Text=" results per page" runat="server" />
               </td>
            </tr>
         </table>
      </PagerTemplate>
   </asp:GridView>
protected void dgCQMainDropDownList_SelectedIndexChanged_Bottom(Object sender, EventArgs e)
{
   // Set the PageIndex property to display that page selected by the user.
   dgCQMain.PageIndex = 0;
   dgCQMain.PageSize = int.Parse((sender as DropDownList).SelectedItem.Value);
}

/// <summary>
/// Special method to handle the Drop down list value changing 
/// but ASP not accurately modifying the controls
/// </summary>
private void HandlePossibleBottomRowEvents()
{
    var page = associatedGridView.Page;
    var request = page.Request;
    var possibleCall = request.Form["__EventTarget"];
    if (possibleCall != null)
    {
        if (possibleCall.Contains("pagerDDL"))
        {
            var newPageSize = request[possibleCall];
            var newSize = int.Parse(newPageSize);
            if (associatedGridView.PageSize != newSize)
                UpdatePageSize(newSize);
        }
    }
}