Change asp:Label text from C# code behind
<p>I've been trying with this for an hour or so; just can't seem to figure out.
I have an <code>asp:Button</code> on an aspx page, required to complete a couple of functions, one of which is to change the text of an <code>asp:Label</code>. This seems like it should be simple and other online posts indicate that I'm approaching the problem correctly but...</p>

<p>The problem is simple but it's killing me. In an effort to debug/troubleshoot, I've stripped the code right back to very basics:</p>

<pre><code>protected void Page_Load(object sender, EventArgs e)
{
    allValidationMsg.Text = "Original text";
}

protected void btnRegister_Click(object sender, EventArgs e)
{
    allValidationMsg.Text = "Text changed";
}
</code></pre>

<p>When the button is clicked, nothing happens. I'm sure it's something simple that I'm missing.</p>

<p>Update:</p>

<pre><code>&lt;asp:Label id="allValidationMsg" runat="server" height="22px" ForeColor="Red"&gt;&lt;/asp:Label&gt;

&lt;asp:Button class="navbutton" ID="btnRegister" runat="server" 
                    Text="Register User" OnClick="btnRegister_Click" /&gt;
</code></pre>
