title: Unity exceptions on load texture with WWW
body: <p>I need to download an image from a server and show in sprite. All example I can find recommended next code:</p>
  
  <pre><code>WWW www = new WWW(requestUrl);
  yield return www;
  onTextureLoaded(www.texture,id);
  </code></pre>
  
  <p>But I can't find the way how to handle exceptions in this case. Should I add Try catch? Or is there any way to check if the request was successful?</p>