Json类型未被识别

Question

为什么我不能把Json送回去。它是加下划线的，在当前情况下不存在。

using System;
using System.Collections.Generic;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using System.Web.Http;
using System.Web.Http.Results;
using System.Web.Mvc;

//class and namespace detail removed to keep this post short

    public async Task<IHttpActionResult> Post(string url, StringContent data, Dictionary<string, string> headers)
    {
        using (var client = new HttpClient())
        {
                var response = await client.PostAsync(url, data);
                var result = await response.Content.ReadAsStringAsync();

                //the line below is the error******** 
                return Json(new { HttpStatusCode = HttpStatusCode.OK });
        }
    }

我也尝试过install-package System.Json，但这没有帮助。

我意识到可能还有其他错误，这段代码从一小时前就开始运行了，但是我不明白为什么Json没有被识别

这来自类库中(如果重要的话)。

Answer 1

该方法是Web的ApiController的助手方法，应该在ApiController派生类中调用。

public class MyApiController : System.Web.Http.ApiController {

    public async Task<IHttpActionResult> Post(string url, StringContent data, Dictionary<string, string> headers) {
        using (var client = new HttpClient()) {
            var response = await client.PostAsync(url, data);
            var result = await response.Content.ReadAsStringAsync();

            return Json(new { HttpStatusCode = HttpStatusCode.OK });
        }
    }    
}

MVC Controller派生类也是如此。

public class MyController : Controller {

    public async Task<ActionResult> Post(string url, StringContent data, Dictionary<string, string> headers) {
        using (var client = new HttpClient()) {
            var response = await client.PostAsync(url, data);
            var result = await response.Content.ReadAsStringAsync();

            return Json(new { HttpStatusCode = HttpStatusCode.OK }, JsonRequestBehavior.AllowGet);
        }
    }    
}