title: Add model to list of another model
body: <p>Model:</p>
  
  <pre><code>public class DataModel1
  {
      public string Id { get; set; }
      public string Name { get; set; }
  }
  
  public class DataModel2
  {
      public string Id { get; set; }
      public string Name { get; set; }
      public string Phone { get; set; }
  }
  </code></pre>
  
  <p>I want to add DataModel1 to DataModel2 as code below.</p>
  
  <pre><code>List&lt;DataModel2&gt; dataModel2List = new List&lt;DataModel2&gt;();
  dataModel2List.Add(db.DataModel1.Select(row =&gt; row).FirstOrDefault()); // The best overloaded method match for 'System.Collections.Generic.List&lt;DataModel2&gt;.Add(DataModel2)' has some invalid arguments.
  </code></pre>