为什么在使用的自定义的pagertemplate的翻页时会触发对页面上控件的有效性验证,急,在线等,先谢了

代码如下:<%@ Page Language="C#" AutoEventWireup="true" CodeFile="test.aspx.cs" Inherits="Admin_WebIdentity_Modules_UserMgr_test" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>无标题页</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
        <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox1"
            ErrorMessage="RequiredFieldValidator"></asp:RequiredFieldValidator>
        <asp:Button ID="Button1" runat="server" Text="Button" /><br />
        <asp:GridView ID="GridView1" runat="server" AllowPaging="True" AutoGenerateColumns="False" DataSourceID="SqlDataSource1">
            <Columns>
                <asp:BoundField DataField="UserID" HeaderText="UserID" InsertVisible="False" ReadOnly="True"
                    SortExpression="UserID" />
                <asp:BoundField DataField="UserName" HeaderText="UserName" SortExpression="UserName" />
                <asp:BoundField DataField="Sex" HeaderText="Sex" SortExpression="Sex" />
                <asp:BoundField DataField="Phone" HeaderText="Phone" SortExpression="Phone" />
                <asp:BoundField DataField="Email" HeaderText="Email" SortExpression="Email" />
                <asp:CommandField ShowDeleteButton="True" ShowEditButton="True" />
            </Columns>
            <pagertemplate>
           <table width="100%">
              <tr>
                <td>
                  <asp:LinkButton id="PreviousButton"
                    text="<"
                    CommandName="Page"
                    CommandArgument="Prev"
                    runat="Server"/>
                  <asp:LinkButton id="NextButton"
                    text=">"
                    CommandName="Page"
                    CommandArgument="Next"
                    runat="Server"/> 
                </td>              </tr>
            </table>          
          </pagertemplate>
        </asp:GridView>
        <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:SqlConnectionString %>" SelectCommand="SELECT [UserID], [UserName], [Sex], [Phone], [Email], FROM [Users]"></asp:SqlDataSource>  </div>
    </form>
</body>
</html>页面中若将
  <pagertemplate>
           <table width="100%">
              <tr>
                <td>
                  <asp:LinkButton id="PreviousButton"
                    text="<"
                    CommandName="Page"
                    CommandArgument="Prev"
                    runat="Server"/>
                  <asp:LinkButton id="NextButton"
                    text=">"
                    CommandName="Page"
                    CommandArgument="Next"
                    runat="Server"/> 
                </td>              </tr>
            </table>          
          </pagertemplate>
去掉,就不会触发有效性验证.我现在需要使用自定义pagertemplate,不知应该如何解决.