title: can't get GET variables
body: <p>I am trying to get the values from GET.  I've been using:</p>
  
  <pre><code>Request.QueryString["$random_var"]
  </code></pre>
  
  <p>with success for a little while now.  Suddenly, this code:</p>
  
  <pre><code>bool preview = (!string.IsNullOrEmpty(Request.QueryString["previewtheme"]));
  </code></pre>
  
  <p>Produces this error:</p>
  
  <pre><code>An object reference is required for the non-static field, method, or property 'System.Web.UI.UserControl.Request.get'
  </code></pre>
  
  <p>I am using the following:</p>
  
  <pre><code>using System.Web;
  using System.Web.Security;
  using System.Web.UI;
  using System.Web.UI.WebControls;
  using System.Web.UI.WebControls.WebParts;
  using System.Web.UI.HtmlControls;
  </code></pre>
  
  <p>Any ideas of what is keeping asp.net from doing this simple task?</p>