title: asp.net MVC 4 SSN Validation
body: <p>I am using ASP.NET MVC 4 and I am looking for an attribute for SSN Validation.  </p>
  
  <pre><code>[Required(ErrorMessage = "Social Security is Required")]
  [SSN]
  public string SSN { get; set; }
  </code></pre>
  
  <p>I know this doesn't work, but this is what I am looking for.</p>
  
  <p>Can anyone Help</p>