HTML
<body>
<form id="form1" runat="server">
<asp:Button runat="server" ID="a" OnClick="a_Click" Text="apd"/>
</form>
</body>
Code
protected void a_Click(object sender,EventArgs e)
{
Response.Write(((Button)FindControl("a")).Text);
}
This code works fine.
However, this code:
HTML
<%@ Page Title="" Language="C#" MasterPageFile="~/Student/MasterPage.master" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="Student_Default" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
<asp:Button runat="server" ID="a" OnClick="a_Click" Text="andj"/>
</asp:Content>
Code
protected void a_Click(object sender, EventArgs e)
{
Response.Write(((Button)FindControl("a")).Text);
}
This code does not work and FindControl returns Null – why is this?
The FindControl method works in a simple page fine, but in a master page, does it not work?
The ID of the a is changed to ctl00_ContentPlaceHolder1_a – how can find control?
To find the button on your content page you have to search for the
ContentPlaceHolder1control first.Then use the
FindControlfunction on theContentPlaceHolder1control to search for your button: