GridView手动分页

下面这段代码放在gridview分页模板里 也就是PagerTemplate这个里

 <PagerTemplate> 
            <asp:LinkButton ID="lbFirst" runat="server" CausesValidation="False"
             CommandArgument="First" CommandName="Page">首页</asp:LinkButton> 
             <asp:LinkButton ID="lbPrev" runat="server" CausesValidation="False"
              CommandArgument="Prev" CommandName="Page">上一页</asp:LinkButton> 
              <asp:LinkButton ID="lbNext" runat="server" CausesValidation="False"
               CommandArgument="Next" CommandName="Page">下一页</asp:LinkButton> 
               <asp:LinkButton ID="lbLast" runat="server" CausesValidation="False"
                CommandArgument="Last" CommandName="Page">尾页</asp:LinkButton> 
                第<asp:Label ID="Label2" runat="server"
                 Text="<%#((GridView)Container.Parent.Parent).PageIndex + 1 %>">
                 </asp:Label>页 共<asp:Label ID="Label1" runat="server" Text="<%# 
                 ((GridView)Container.Parent.Parent).PageCount %>"></asp:Label>页
                  跳到<asp:TextBox ID="tbPage" runat="server"
                   Text="<%# ((GridView)Container.Parent.Parent).PageIndex + 1 %>" Width="27px"></asp:TextBox>
                    <asp:LinkButton ID="lbGO" runat="server" CausesValidation="False" CommandArgument="-1" CommandName="Page" Text="GO">
                    </asp:LinkButton> 
            </PagerTemplate> 


 protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        GridView gvw = (GridView)sender; 
        if (e.NewPageIndex < 0) 
        { 
            TextBox pageNum = (TextBox)gvw.BottomPagerRow.FindControl("tbPage"); 
            int Pa = int.Parse(pageNum.Text); 
            if (Pa <= 0) gvw.PageIndex = 0;