Webapi Post has null values

Question

我正在从另一个项目（C#类）调用webApi，其中一个属性始终为null。我在调试时验证了对象是否已正确填充。正在传递的对象存储在两个项目中都引用的共享库中。因此，类型不应该不匹配。

我在邮寄订单之前核实。产品。答案已设置。那么我在WebApi方法中有一个断点，它为null。我不知道为什么。

以下是用于生成帖子的代码：

    [HttpPost]
    public ActionResult Add(ApiOrder order)
    {
        try
        {
            HttpResponseMessage resp = null;
            ApiOrder processedOrder = null;
            using (var client = new HttpClient())
            {
                var url = GetUrlToWebApis();
                client.BaseAddress = new Uri(url);
                client.DefaultRequestHeaders.Accept.Clear();
                client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
                Task<HttpResponseMessage> task = client.PostAsJsonAsync("apisecure/order", order);
                //resolve the reque
                resp = task.Result;
                var a = resp.Content.ReadAsAsync<ApiOrder>();
                processedOrder = a.Result;
                TempData["ConfirmMessage"] = "Order Was added";
            }
            return View("Add", processedOrder);
        }
        catch (Exception e)
        {
            //ViewBag.messgae = e.InnerException;
            TempData["ErrorMessage"] = e.InnerException;
            return View("Add", order);
        }
    }

这是处理后的WebApi方法

public IHttpActionResult Post(ApiOrder order)

这是ApiOrder 的类结构

 [DataContract]
    [System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
    public class ApiOrder
    {
        [DataMember]
        [Required]
        public virtual int Id { get; set; }
        [DataMember]
        // [Required]
        public virtual List<ApiProduct> Products { get; set; }
}

现在ApiProduct类

    [DataContract]
    [System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
    public class ApiProduct
    {
        [DataMember]
        [Required]
        public virtual int ActionId { get; set; }
        [DataMember]
        public virtual List<ApiAnswer> Answers { get; set; } // <-- Always null
}

最后是ApiAnswer

[DataContract]
[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
public class ApiAnswer
{
    [DataMember]
    [Required]
    public virtual int QuestionId { get; set; }
    [DataMember]
    public virtual string QuestionText { get; set; }
    [DataMember]        
    public virtual string Answer { get; set; }
}

Answer 1

啊，问题是我有两个解决方案，其中一个垃圾箱有一个过期的dll。清洁和重建这两种解决方案都解决了这个问题。