ASP.NET 5, MVC6, WebAPI -> ModelState.IsValid always returns true
<p>I've seen a lot of posts about IsValid always being true but none of them have helped me solve this problem.  I'm also seeing this problem in ASP.NET 4 using MVC5.  So clearly I'm missing a step somewhere.</p>

<p>Controller method:</p>

<pre><code>public IHttpActionResult Post([FromBody]ValuesObject value)
{
    if (ModelState.IsValid)
    {
        return Json(value);
    }
    else
    {
        return Json(ModelState);
    }
}
</code></pre>

<p>ValuesObject Class:</p>

<pre><code>public class ValuesObject
{
    [Required]
    public string Name;

    [Range(10, 100, ErrorMessage = "This isn't right")]
    public int Age;
}
</code></pre>

<p>Body of the POST:</p>

<pre><code>{
  Age: 1
}
</code></pre>

<p>ModelState.IsValid is true.</p>

<p>But I would expect both the Required and Range validations to fail.</p>

<p>What am I missing??</p>

<p>Thanks,</p>

<p>Kevin</p>