title: asp.net mvc: TryUpdateModel return value or ModelState.IsValid?
body: <p>Doing validation in my binder, I'm wondering if there's a need to check the return value.  In Option 1 below, is there ever going to be a difference in case 1 and case 2?  It doesn't seem possible that TryUpdateModel would return true, but ModelState.IsValid is false.</p>
  
  <p>Option 1:</p>
  
  <pre><code>  if (TryUpdateModel(editItem, new string[] { "Field" }))
    {
      if (ModelState.IsValid)
      {
      } else {
      // Invalid model case 1
    }
    } else {
      // Invalid model case 2
    }
  </code></pre>
  
  <p>Option 2:</p>
  
  <pre><code>  TryUpdateModel(editItem, new string[] { "Field" }))
    if (ModelState.IsValid)
    {
    } else {
      // only one invalid model case 
    }
  </code></pre>