How to find header control of repeater in c# .net?
<p>I am working on asp.net c# . I am trying to find the header control in c# . But I am getting object not set to an instance of an object . My code is </p>

<pre><code>    public void R1_ItemDataBound(Object Sender, RepeaterItemEventArgs e)
    {
        if (e.Item.ItemType == ListItemType.Header)
        {
            HtmlGenericControl ulSubNav2 = (HtmlGenericControl)e.Item.FindControl("da-sliders");
            ulSubNav2.Style.Add("background", "transparent url('DesktopModules/DNAiusParallelSlider/Images/waves.gif') repeat 0% 0%");
            ulSubNav2.Style.Add("width", "100%");
            ulSubNav2.Style.Add("height", "400px");
        }
    }
</code></pre>

<p>relevant HTML Code</p>

<pre><code>  &lt;HeaderTemplate&gt; 
      &lt;div id="da-sliders" class="da-slider" OnItemDataBound="R1_ItemDataBound"&gt;
  &lt;/HeaderTemplate&gt;
</code></pre>
