ASP.NET content incode id

I recently started using Masterpages, the thing is I would like to add text in code to an asp:Content tag.

So my content page markup code is:

<%@ Page Language="C#" MasterPageFile="~/Template.Master" AutoEventWireup="true" C开发者_Go百科odeBehind="Default.aspx.cs" Inherits="ASP_Test_WebApp.Default" %>
<asp:Content id="TEST" ContentPlaceHolderID="Main" Runat="Server" />

So now I would like to add Contents to the "TEST" id incode.

But my in code doesn't recognize TEST. If I don't use a masterpage and I give an id to a tag my in code reconigzes it, but now that I started using masterpages it doesn't.

What am I doing wrong?

Content tags don't have any UI on their own, you need to add controls inside them that you can then address in your code e.g.

<%@ Page Language="C#" MasterPageFile="~/Template.Master" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="ASP_Test_WebApp.Default" %> 
<asp:Content id="TEST" ContentPlaceHolderID="Main" Runat="Server" >
    <asp:label runat="server" id="MyLabel"/>
</asp:content>

public partial class Default: System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        MyLabel.Text = "StackOverflow rocks!"
    }
}

You don't need that ID. Try to add your content like: this.Controls.Add(mycontentcontrol)