title: asp.net submitdate showing up as required field when its not
body: <p>I have the following model in my ASP.NET application. I had a required validator on SubmitDate but have since removed it. However when I try to submit an entry into my DB via the web field, I still get a "SubmitDate is a required field". </p>
  
  <pre><code>namespace dev_apps.Models
  {
      public class App
      {
          public int ID { get; set; }
          [DisplayFormat(DataFormatString = "{0:d}")]
          public DateTime SubmitDate { get; set; }
          public virtual string Entry { get; set; }
  
      }
  
      public class AppDBContext : DbContext
      {
          public DbSet&lt;App&gt; Apps { get; set; }
      }
  }
  </code></pre>
  
  <p>Looking at the db (apps.sdf) the column properties for SubmitDate shows Allow Null = False. But I am unable to change this (its grayed out). </p>
  
  <p>Any help is much appreciated.</p>