title: ASP.NET MVC 5 - Model Binding Not Working
body: <p>I am having trouble binding incoming JSON data in the body of an HTTP POST request to my C# model.</p>
  
  <p>Here is my front-end JavaScript code:</p>
  
  <pre><code>let jsonData = "{\"Updates\":[{\"CarrierStateMapGuid\":\"de4abaa8-42d2-4e00-657a08d5577ac94a\",\"QuestionTag\":\"CoQstPAVT500006\",\"MemberOf\":\"Quote\",\"Condition\":\"0\",\"QuestionType\":\"List\",\"TrueAnswer\":\"NoDiscount\",\"TrueExplanation\":\"No Discount\",\"FalseAnswer\":null,\"FalseExplanation\":null,\"DeleteRequest\":false}]}";
  $.ajax({
      url: "/api/CarrierQuestionMappingApi/UpdateQuestionMaps",
      type: "POST",
      contentType: "application/json; charset=utf-8",
      data: jsonData
  });
  </code></pre>
  
  <p>Here is my C# model:</p>
  
  <pre><code>public class UpdateCarrierQuestionMapsWebRequests
  {
      public UpdateCarrierQuestionMapsWebRequest[] Updates { get; set; }
  
      public class UpdateCarrierQuestionMapsWebRequest
      {
          public string CarrierStateMapGuid { get; set; }
          public string QuestionTag { get; set; }
          public string MemberOf { get; set; }
          public string Condition { get; set; }
          public string QuestionType { get; set; }
          public string TrueAnswer { get; set; }
          public string TrueExplanation { get; set; }
          public string FalseAnswer { get; set; }
          public string FalseExplanation { get; set; }
          public bool DeleteRequest { get; set; }
      }
  }
  </code></pre>
  
  <p>Here is my back-end C# controller code:</p>
  
  <pre><code>[HttpPost]
  [Route("api/[controller]/UpdateQuestionMaps")]
  public HttpResponseMessage UpdateQuestionMaps(UpdateCarrierQuestionMapsWebRequests request)
  {
       // request.Updates is null
  }
  </code></pre>
  
  <p>I cannot figure out why request.Updates is null and is not getting set by the model binder.</p>