title: Find control that reside in other assembly
body: <p>I have 1 solution that contain a reference to other dll class <code>fatherWeb</code></p>
  
  <p>I am trying to "find" a control that resides inside this dll.
  In <code>Page_Load</code> event I am trying to get reference to control in <code>Header</code> of the <code>fatherWeb.dll</code>.
  In fatherWeb Class, there is a page called <code>UserNew.Master</code> in that page <code>head</code> section there is a <code>asp:contentPlaceHolder</code> control with the ID of <code>ContentHead</code>:</p>
  
  <pre><code>&lt;head&gt;
      &lt;asp:ContentPlaceHolder ID="ContentHead" runat="server"&gt;
      &lt;/asp:ContentPlaceHolder&gt;  
  &lt;/head&gt;
  </code></pre>
  
  <p>In the second project that is loading <code>faterWeb.dll</code>
  i am trying to get reference to the <code>asp:contentPlaceHolder</code> control with the id <code>ContentHead</code> using this code:</p>
  
  <pre><code> var pageHeader = Page.FindRecursiveControl&lt;fatherWeb.UserNew.ContentHead&gt;();
  </code></pre>
  
  <p>But i am getting <code>null</code>.</p>
  
  <p>Also tried this:</p>
  
  <pre><code>Page.FindRecursiveControl&lt;faterWeb.UserNew&gt;().FindControl("ContentHead")
  </code></pre>
  
  <p>and also</p>
  
  <pre><code>Page.FindRecursiveControl&lt;faterWeb.PageHeader&gt;()
  </code></pre>
  
  <p>But is resulted in that error:</p>
  
  <blockquote>
    <p>Page.FindRecursiveControl()  The call is ambiguous between the following methods or properties: 'AI.ScriptManager.Extension.ControlExtension.FindRecursiveControl(System.Web.UI.Page)' and 'AI.ScriptManager.Extension.ControlExtension.FindRecursiveControl(System.Web.UI.Page)'  </p>
  </blockquote>
  
  <p><code>faterWeb.PageHeader</code> "PageHeader" suppose to be a page (ascx, aspx)in this dll? </p>
  
  <p>If so this is not the right class name that i am looking. the right one is called  <code>UserNew.Master</code> which holds <code>&lt;asp:ContentPlaceHolder ID="ContentHead" runat="server"&gt;</code> and this is the control i am trying to get..</p>
  
  <p>How can i get it right?</p>