title: How do I define usings in MVC 3 Razor View Engine across entire site?
body: <p>I wrote a simple extension method for UrlHelper:</p>
  
  <pre><code>public static class ExtensionMethods
  {
      private const string ImagesFolder = "~/Images";
  
      public static string Images(this UrlHelper url)
      {
          return url.Content(ImagesFolder);
      }
  }
  </code></pre>
  
  <p>The above code resides in <code>/Helper/ExtensionMethods.cs</code>. It works just fine but I need to add <code>using MyNamespace.Helper;</code> in every cshtml where I want to use the <code>Url.Images()</code>. I the old days we would add another line to <code>web.config</code>:</p>
  
  <pre><code>&lt;system.web&gt;
      &lt;pages&gt;
          &lt;namespaces&gt;
              &lt;add namespace="MyNamespace.Helper"/&gt;
          &lt;/namespaces&gt;
      &lt;/pages&gt;
  &lt;/system.web&gt;
  </code></pre>
  
  <p>But the above does not seem to be picked up by Razor. I tried adding my using statement to <code>_ViewStart.cshtml</code>, with the same result.</p>
  
  <p>So, what's Razor's way of specifying a using across the entire site?</p>