title: Get custom property types using Reflection
body: <p>Suppose I have a class (something like this):</p>
  
  <pre><code>public class User
  {
     public Guid Id { get; set;}
     public DateTime CreationDate { get; set; }
     public string Name { get; set; }
     public UserGroup Group { get; set; } 
  }
  </code></pre>
  
  <p>Is there a way get all property types that are not part of the .NET Framework.
  So in this case I want to get only <code>UserGroup</code> ? Is that possible ?</p>
  
  <p>The best thing I can come up with is something like:</p>
  
  <p><code>IEnumerable&lt;Type&gt; types = typeof(User).GetProperties().Where(p =&gt; !p.PropertyType.Namespace.StartsWith("System.")).Select(t =&gt; t.PropertyType);</code></p>
  
  <p>But this looks like a hack-job. Sorry if dup, couldn't find anything like that, and sorry for the formatting, did my best.</p>