title: ASP WebAPI generic List optional parameter
body: <p>I'm really struggling with this one. I need a generic list parameter for my Get method, but it needs to be optional. I just did this:</p>
  
  <pre><code>public dynamic Get(List &lt;long&gt; ManufacturerIDs = null)
  </code></pre>
  
  <p>Unfortunately on runtime i get the error:</p>
  
  <blockquote>
    <p>Optional parameter 'ManufacturerIDs' is not supported by
    'FormatterParameterBinding'.</p>
  </blockquote>
  
  <p>How to get a generic list as an optional parameter here?</p>