title: Table not mapped using EF code first approach
body: <p>I'd like to use <code>EF code first approach</code>. I added the database and I generate the tables . Then I added this class</p>
  <pre><code>  public class Invitation
      {
  
        
          [Key]
          public int Id { get; set; }
  
          [DefaultValue(false)]
          public bool State { get; set; }
  
          public string Mail { get; set; }
  
          public string Tel { get; set; }
  
          public string Name { get; set; }
  
          public string Qr_code { get; set; }
    
      }
  </code></pre>
  <p>I run these command then  :</p>
  <blockquote>
  <p>add-migrations second</p>
  <p>update-database</p>
  </blockquote>
  <p>the <code>Up</code> and <code>Down</code> methods of the second class migration are empty!! and no table is added to the database.</p>
  <p><strong>The context</strong></p>
  <pre><code> public class ApplicationContext: IdentityDbContext&lt;ApplicationUser&gt;
      {
           public ApplicationContext()
              :base(&quot;DefaultConnection&quot;)
          {
              Database.SetInitializer&lt;ApplicationContext&gt;(new CreateDatabaseIfNotExists&lt;ApplicationContext&gt;());
          }
  
          public static ApplicationContext Create()
          {
              return new ApplicationContext();
          }
  
          protected override void OnModelCreating(DbModelBuilder modelBuilder)
          {
              base.OnModelCreating(modelBuilder);
          }
      }
  </code></pre>
  <p>So I need to know</p>
  <ol>
  <li>What is the reason of this problem?</li>
  <li>How can I fix it?</li>
  </ol>