web api JSON Model为null

Question

当我将json响应发送回我的api时，模型报告为null并且不会更新。我已将Content-Type设置为application / json

请求：

  

[{＆＃34; SurveyID＆＃34;：＆＃34; 55＆＃34;，＆＃34; QuestionID＆＃34;：＆＃34; 4＆＃34;，＆＃34;回复＆＃34;： 6}，{＆＃34; SurveyID＆＃34;：＆＃34; 55＆＃34;，＆＃34; QuestionID＆＃34;：＆＃34; 12＆＃34;，＆＃34;回复＆＃34;：＆ ＃34; 1＆＃34;}]

控制器：

public HttpResponseMessage Post([FromUri] Response response)
{
    try
    {
        if (ModelState.IsValid)
        {
            using (NPSEntities entities = new NPSEntities())
            {
                entities.Responses.Add(response);
                entities.SaveChanges();
                return Request.CreateResponse(HttpStatusCode.OK);
            }
        }
        else
        {
            return Request.CreateResponse(HttpStatusCode.InternalServerError, "Invalid Model");
        }
    }
    catch (Exception ex)
    {
        return Request.CreateResponse(HttpStatusCode.InternalServerError, ex.Message);
        throw;
    }
}

模型：

public partial class Response
{
    public int ResponseID { get; set; }
    public string SurveyID { get; set; }
    public string QuestionID { get; set; }
    public string Responses { get; set; }
    public Nullable<System.DateTime> ModifyDate { get; set; }
}