New ASP.NET Web Application: has a Login button that does something - but, where does the magic happen?
<p>Forgive my somewhat-lacking ASP.NET knowledge for this question :)  </p>

<p>Here's the scenario: I'm playing around in VS2010, I've created a new <code>ASP.NET Web Application</code> (under Visual C#, Web templates). Nothing special, just a basic web application. No fancy MVC stuff.  </p>

<p>Included in the template-generated solution is a Login page; <code>Account/Login.aspx</code>. On that page, is a Login button; the HTML looks like this:  </p>

<pre><code>&lt;p class="submitButton"&gt;
    &lt;asp:Button ID="LoginButton"
                runat="server"
                CommandName="Login"
                Text="Log In"
                ValidationGroup="LoginUserValidationGroup"/&gt;
&lt;/p&gt;
</code></pre>

<p>Again, nothing fancy. Now, the code behind:  </p>

<pre><code>using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class Account_Login : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        RegisterHyperLink.NavigateUrl = "Register.aspx?ReturnUrl=" + HttpUtility.UrlEncode(Request.QueryString["ReturnUrl"]);
    }
}
</code></pre>

<p>Even less fancy. And finally, from web.config:</p>

<pre><code>    &lt;authentication mode="Forms"&gt;
        &lt;forms loginUrl="~/Account/Login.aspx" timeout="2880"/&gt;
    &lt;/authentication&gt;
</code></pre>

<p>So, <strong>here is what I can't quite figure out</strong>: when I run the app, I can click the <em>Login</em> button, and the app does <em>something</em> - but where is the code for that <em>something</em>?  </p>

<p>Coming from the WPF world (with some background in ASP.NET), my first instinct is to zero-in on <code>CommandName</code> - but a search for anything relating to "Login" turns up dry. My second instinct is to look at the code-behind, but again, it's pretty sparse and I don't see anything that looks like it has anything to do with a Login button being clicked.  </p>

<p>So where does the "magic" behind this button happen? There has to be <em>something</em>; I feel like I've overlooked something that is sitting right in front of my eyes. </p>
