title: What is the difference between, IsAssignableFrom and GetInterface?
body: <p>Using reflection in .Net, what is the differnce between:</p>
  
  <pre><code>   if (foo.IsAssignableFrom(typeof(IBar)))
  </code></pre>
  
  <p>And</p>
  
  <pre><code>   if (foo.GetInterface(typeof(IBar).FullName) != null)
  </code></pre>
  
  <p>Which is more appropriate, why?<br></p>
  
  <p>When could one or the other fail?</p>