.NET中使用GridView控件，再用<PagerTemplate>模版做分页功能，可是在浏览器中显示不出<PagerTemplate>中所有的控件

前台代码如下：
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource1"
            Height="111px" Width="764px" OnRowDataBound="GridView1_RowDataBound" OnSelectedIndexChanged="GridView1_SelectedIndexChanged"
            OnRowEditing="GridView1_RowEditing" OnRowUpdating="GridView1_RowUpdating" OnRowCancelingEdit="GridView1_RowCancelingEdit"
            PageSize="8" OnPageIndexChanging="GridView1_PageIndexChanging" AllowSorting="True"
            align="center" Style="text-align: center" AllowPaging="True">
            <Columns>
                <asp:TemplateField HeaderText="选择">
                    <ItemTemplate>
                        <asp:CheckBox ID="chkSelect" runat="server" OnClick="checkbox_onchange()" />
                    </ItemTemplate>
                </asp:TemplateField>
                <asp:TemplateField HeaderText="序号">
                    <ControlStyle Width="30px" />
                    <EditItemTemplate>
                        <asp:TextBox ID="edID" runat="server" Text='<%# Bind("RolesId") %>'></asp:TextBox>
                    </EditItemTemplate>
                    <ItemTemplate>
                        <asp:Label ID="lbID" runat="server" Text='<%# Bind("RolesId") %>'></asp:Label>
                    </ItemTemplate>
                    <FooterTemplate>
                        <asp:TextBox ID="txtID" runat="server"></asp:TextBox>
                    </FooterTemplate>
                </asp:TemplateField>
                <asp:TemplateField HeaderText="角色">
                    <ControlStyle Width="100px" />
                    <EditItemTemplate>
                        <asp:DropDownList ID="edRolesName" runat="server" DataSourceID="SqlDataSource1" DataTextField="RolesName"
                            DataValueField="RolesId" AutoPostBack="True" AppendDataBoundItems="True">
                        </asp:DropDownList>
                    </EditItemTemplate>
                    <ItemTemplate>
                        <asp:Label ID="lbRolesName" runat="server" Text='<%# Bind("RolesName") %>'></asp:Label>
                    </ItemTemplate>
                    <FooterTemplate>
                        <asp:TextBox ID="txtRolesName" runat="server" Width="100px"></asp:TextBox>
                    </FooterTemplate>
                </asp:TemplateField>
                <asp:CommandField HeaderText="编辑" ShowEditButton="True" ControlStyle-ForeColor="Red">
                    <ControlStyle ForeColor="Red"></ControlStyle>
                </asp:CommandField>
            </Columns>
            <RowStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" CssClass="gvRow" />
            <EditRowStyle BorderColor="Red" Font-Underline="False" ForeColor="Red" />
            <HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#F7F7F7" CssClass="gvHeader" />
            <AlternatingRowStyle BackColor="#F7F7F7" CssClass="gvAlternatingRow" />
            <PagerTemplate>
                <table width="100%">
                    <tr>
                        <td align="left">
                            <asp:Button ID="btnFirst" runat="server" Text="首 页" Height="20px" CssClass="buttonup2"
                                OnClick="btnFirst_Click" UseSubmitBehavior="False" onmouseout="this.style.background ='url(images/mouseup2.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown2.jpg)'" />
                            <asp:Button ID="btnPre" runat="server" Text="上一页" Height="20px" CssClass="buttonup2"
                                OnClick="btnPre_Click" UseSubmitBehavior="False" onmouseout="this.style.background ='url(images/mouseup2.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown2.jpg)'" />
                            <asp:Button ID="btnNext" runat="server" Text="下一页" Height="20px" CssClass="buttonup2"
                                OnClick="btnNext_Click" UseSubmitBehavior="False" onmouseout="this.style.background ='url(images/mouseup2.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown2.jpg)'" />
                            <asp:Button ID="btnLast" runat="server" Text="尾 页" Height="20px" CssClass="buttonup2"
                                OnClick="btnLast_Click" UseSubmitBehavior="False" onmouseout="this.style.background ='url(images/mouseup2.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown2.jpg)'" />
                        </td>
                        <td align="center">
                            当前第<asp:Label ID="LblPage" runat="server" Style="text-align: center" Text='<%# GridView1.PageIndex + 1%>'></asp:Label>
                            页/共<asp:Label ID="LblTotalPage" runat="server" Style="text-align: center;" Text='<%# GridView1.PageCount %>'></asp:Label>
                            页
                            <%--<asp:Label ID="lblCurrentPage" Height="20px" runat="server" Text="Label"></asp:Label>--%>
                            <asp:Label runat="server" Height="20px" Text="跳转到第"></asp:Label>
                            <asp:DropDownList Height="20px" ID="ddlCurrentPage" runat="server" AutoPostBack="True"
                                OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
                            </asp:DropDownList>
                            <asp:Label ID="Label1" runat="server" Height="20px" Text="页"></asp:Label>
                        </td>
                        <td align="right">
                            <asp:CheckBox ID="CheckBox2" runat="server" Height="20px" OnCheckedChanged="CheckBox2_CheckedChanged"
                                Text="全选" AutoPostBack="True" />
                            <asp:Button ID="btnAdd" runat="server" Height="20px" Text="添加角色" CssClass="buttonup4"
                                OnClick="btnAdd_Click" UseSubmitBehavior="False" onmouseout="this.style.background ='url(images/mouseup4.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown4.jpg)'" />
                            <asp:Button ID="btnSave" runat="server" Height="20px" Text="提 交" CssClass="buttonup2"
                                OnClick="btnSave_Click" UseSubmitBehavior="False" onmouseout="this.style.background ='url(images/mouseup2.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown2.jpg)'" />
                            <asp:Button ID="btnDelete" runat="server" Height="20px" Text="删 除" OnClick="btnDelete_Click"
                                CssClass="buttonup2" OnClientClick="return confirm('确认修改提交吗？')" onmouseout="this.style.background ='url(images/mouseup2.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown2.jpg)'" />
                            <asp:Button ID="btnCancle" runat="server" Height="20px" Text="取 消" OnClick="btnCancle_Click"
                                UseSubmitBehavior="False" CssClass="buttonup2" onmouseout="this.style.background ='url(images/mouseup2.jpg)'"
                                onmouseover="this.style.background ='url(images/mousedown2.jpg)'" />
                        </td>
                    </tr>
                </table>
            </PagerTemplate>
        </asp:GridView>
        <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:TPHConnectionString %>"
            SelectCommand="SELECT * FROM [TPH_Roles]"></asp:SqlDataSource>
    </div>