Custom User Control in UpdatePanel forcing Postback
<p>I have a custom user control that has an event (SelectedUserChanged). I have this control inside an UpdatePanel but when the control executes the event, the entire page does a postback instead of just the update panel. What in the world do I have going on?</p>

<p>My User Control:</p>

<pre><code>public delegate void SelectedUserChangedHandler(object sender, WebUserBrowserEventArgs e);

public event SelectedUserChangedHandler SelectedUserChanged;

protected void Page_Load(object sender, EventArgs e)
{
    if (Request["__EventTarget"] != null &amp;&amp; Request["__EventTarget"] == "UcWebUserBrowser" &amp;&amp; Request["__EventArgument"] != null)
    {
        int webUserID = Int32.Parse(Request["__EventArgument"]);
        if(SelectedUserChanged != null)
            SelectedUserChanged(this, new WebUserBrowserEventArgs(webUserID));
        //
    }
}
</code></pre>

<p>My Update Panel:</p>

<pre><code>&lt;asp:UpdatePanel ID="updatePanelOpportunityLeaderContainer" runat="server"&gt;
 &lt;ContentTemplate&gt;
  &lt;custom:UcWebUserBrowser ID="ucWebUserBrowserOpportunityLeader" runat="server" /&gt;
 &lt;/ContentTemplate&gt;
&lt;/asp:UpdatePanel&gt;
</code></pre>
