子页嵌套了三层母版页后，依次访问第一层、第二层、第三层母版页控件的实现方法如下：
第一层母版页HTML代码
<%@ Master Language="C#" AutoEventWireup="true" CodeFile="MasterPage.master.cs" Inherits="MasterPage_MasterPage" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">
<html xmlns=""><head runat="server"> <title>MasterPage</title> <asp:ContentPlaceHolder ID="head" runat="server"> </asp:ContentPlaceHolder></head><body> <form id="form1" runat="server"> <div> 第一层母版页 <br /> <asp:Label ID="Master_Label" runat="server" Text="母版页(Label)"></asp:Label> <br /> <br /> <asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server"> </asp:ContentPlaceHolder> </div> </form></body></html>第二层母版页HTML代码
<%@ Master Language="C#" MasterPageFile="~/MasterPage/MasterPage.master" AutoEventWireup="true"
CodeFile="MasterPage2.master.cs" Inherits="MasterPage_MasterPage2" %><asp:Content ID="Content1" ContentPlaceHolderID="head" runat="Server">
<%--添加第二层母版页的子页内容--%> <asp:ContentPlaceHolder ID="head2" runat="Server"> </asp:ContentPlaceHolder></asp:Content><asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server"> 第二层母版页 <br /> <asp:Label ID="Master2_Label" runat="server" Text="母版页2（Label）"></asp:Label> <br /> <br /> <%--添加第二层母版页的子页内容--%> <asp:ContentPlaceHolder ID="ContentPlaceHolder2" runat="Server"> </asp:ContentPlaceHolder></asp:Content>第三层母版页HTML代码
<%@ Master Language="C#" MasterPageFile="~/MasterPage/MasterPage2.master" AutoEventWireup="true"
CodeFile="MasterPage3.master.cs" Inherits="MasterPage_MasterPage3" %><%-- Add content controls here --%>
<%--定义第三层母版页的内容项--%><asp:Content ID="Content1" ContentPlaceHolderID="head2" runat="Server"> <asp:ContentPlaceHolder ID="head3" runat="Server"> </asp:ContentPlaceHolder></asp:Content><%--定义第三层母版页的内容项--%><asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder2" runat="Server"> 第三层母版页 <br /> <asp:Label ID="Master3_Label" runat="server" Text="母版页3（Label）"></asp:Label> <br /> <br /> <asp:ContentPlaceHolder ID="ContentPlaceHolder3" runat="Server"> </asp:ContentPlaceHolder></asp:Content>子页前台HTML代码
<%@ Page Title="" Language="C#" MasterPageFile="~/MasterPage/MasterPage3.master" AutoEventWireup="true" CodeFile="SubPage3.aspx.cs" Inherits="MasterPage_SubPage3" %>
<%-- Add content controls here --%>
<%--继承第三层母版页的正文内容--%><asp:Content ID="Content1" ContentPlaceHolderID="head3" runat="Server"></asp:Content><%--继承第三层母版页的正文内容--%><asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder3" runat="Server"> 子页--333 <br /> <asp:Label ID="Sub3_Label" runat="server" Text="Label"></asp:Label> <br /> <br /> <asp:Button ID="Button1" runat="server" Text="子页3访问母页3" οnclick="Button1_Click" /> <asp:Button ID="Button2" runat="server" Text="子页3注销母页3" οnclick="Button2_Click" /> <br /> <br /> <asp:Button ID="Button3" runat="server" Text="子页3访问母页2" οnclick="Button3_Click" /> <asp:Button ID="Button4" runat="server" Text="子页3注销母页2" οnclick="Button4_Click" /> <br /> <br /> <asp:Button ID="Button5" runat="server" Text="子页3访问母页1" οnclick="Button5_Click" /> <asp:Button ID="Button6" runat="server" Text="子页3注销母页1" οnclick="Button6_Click" /> <br /></asp:Content>子页后台CS代码
using System;
using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;public partial class MasterPage_SubPage3 : System.Web.UI.Page
{ protected void Page_Load(object sender, EventArgs e) {}
//访问第三层母板控件
//登陆 protected void Button1_Click(object sender, EventArgs e) { //从第三层得到第一层的ContentPlaceHolder，来访问其中的控件（此时已为第二层） ContentPlaceHolder cpMaster1 = (ContentPlaceHolder)Master.Master.Master.FindControl("ContentPlaceHolder1"); //第一层母板找到第二层母板的ContentPlaceHolder，来访问其中的控件（此时已为第三层） ContentPlaceHolder cpMaster2 = (ContentPlaceHolder)cpMaster1.FindControl("ContentPlaceHolder2"); Label m3Label = (Label)cpMaster2.FindControl("Master3_Label"); m3Label.Text = "子页3 - 访问母版页3"; } //注销 protected void Button2_Click(object sender, EventArgs e) { //从第三层得到第一层的ContentPlaceHolder，来访问其中的控件（此时已为第二层） ContentPlaceHolder cpMaster1 = (ContentPlaceHolder)Master.Master.Master.FindControl("ContentPlaceHolder1"); //第一层母板找到第二层母板的ContentPlaceHolder，来访问其中的控件（此时已为第三层） ContentPlaceHolder cpMaster2 = (ContentPlaceHolder)cpMaster1.FindControl("ContentPlaceHolder2"); Label m3Label = (Label)cpMaster2.FindControl("Master3_Label"); m3Label.Text = "母版页3(Label)"; }//访问第二层母板控件
//登陆 protected void Button3_Click(object sender, EventArgs e) { //从第三层得到第一层的ContentPlaceHolder，来访问其中的控件（此时已为第二层） ContentPlaceHolder cpMaster1 = (ContentPlaceHolder)Master.Master.Master.FindControl("ContentPlaceHolder1"); Label m2Label = (Label)cpMaster1.FindControl("Master2_Label"); m2Label.Text = "子页3 - 访问母版页2"; } //注销 protected void Button4_Click(object sender, EventArgs e) { //从第三层得到第一层的ContentPlaceHolder，来访问其中的控件（此时已为第二层） ContentPlaceHolder cpMaster1 = (ContentPlaceHolder)Master.Master.Master.FindControl("ContentPlaceHolder1"); Label m2Label = (Label)cpMaster1.FindControl("Master2_Label"); m2Label.Text = "母版页2(Label)"; }//访问第一层母板控件
//登陆 protected void Button5_Click(object sender, EventArgs e) { Label mLabel = (Label)Master.Master.Master.FindControl("Master_Label"); mLabel.Text = "子页3 - 访问母版页1"; } //注销 protected void Button6_Click(object sender, EventArgs e) { Label mLabel = (Label)Master.Master.Master.FindControl("Master_Label"); mLabel.Text = "母版页1(Label)"; }}