HttpClient 传递多个简单参数

Question

我正在尝试从一个controller 到另一个controller 执行POST。两个controller 都来自不同的项目。一个项目用于模拟表示层（我将这里称为测试项目）。

从测试项目中，我尝试将 2 个简单的 string 参数传递给另一个我将调用该过程的控制器。

var values = new List<KeyValuePair<string, string>>();
values.Add(new KeyValuePair<string, string>("id", param.Id.Value));
values.Add(new KeyValuePair<string, string>("type", param.Type.Value));
var content = new FormUrlEncodedContent(values);
using (var client = new HttpClient())
{
       client.BaseAddress = new Uri(url);
       client.DefaultRequestHeaders.Clear();
       client.DefaultRequestHeaders.AcceptLanguage.Add(new StringWithQualityHeaderValue("nl-NL"));

       client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

       string token = param.token.Value;
       client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);

       var response = client.PostAsync("/api/Process/Product", content).Result;

       if (response.IsSuccessStatusCode)
       {
           var result = response.Content.ReadAsStringAsync().Result;
           return Request.CreateResponse(HttpStatusCode.OK, result);
       }

       return Request.CreateErrorResponse(HttpStatusCode.BadRequest, "fail");
}

在进程控制器中，我试图像这样接收它：

[HttpPost]
public HttpResponseMessage Product(string id, string type)
{
    return null;
}

但它永远不会到达这个controller。我总是收到“未找到状态码”。

那么如何使用HttpClient() 传递两个简单的参数？

Answer 1

对简单类型参数使用 Get 而不是 Post。

    using (var client = new HttpClient())
    {
        BaseAddress = new Uri(url);
        client.BaseAddress = new Uri(url);
   client.DefaultRequestHeaders.Clear();
   client.DefaultRequestHeaders.AcceptLanguage.Add(new StringWithQualityHeaderValue("nl-NL"));

   client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

   string token = param.token.Value;
   client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);

        // New code:
        var response = await client.GetAsync( string.format("api/products/id={0}&type={1}",param.Id.Value,param.Id.Type) );
 if (response.IsSuccessStatusCode)
   {
       var result = response.Content.ReadAsStringAsync().Result;
       return Request.CreateResponse(HttpStatusCode.OK, result);
   }

   return Request.CreateErrorResponse(HttpStatusCode.BadRequest, "fail");

    }

在 API 端你可以这样做。

[HttpGet]
public HttpResponseMessage Product(string id, string type)
{
  return null;
}

Answer 2

接收帖子时，必须在参数中指定 [FromBody] 以调用方法

[HttpPost]
public HttpResponseMessage Product([FromBody]string id, [FromBody]string type)
{
    return null;
}

Answer 3

我不确定我是否完全爱上了它，但我过去使用匿名类型和动态来处理这个......（注意使用 PostAsJsonAsync() 的配置差异。我最初忘记了这些。）

client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));    
client.PostAsJsonAsync("api/User/UpdateLastLogin", new { UserId = userId, ApplicationId = applicationId });

接收控制器：

    [HttpPost]
    public void UpdateLastLogin([FromBody]dynamic model)
    {
        _userRepository.UpdateLastLogin((int)model.UserId, (int)model.ApplicationId);
    }

在 WebApiConfig.Register() 中：

var json = config.Formatters.JsonFormatter;
json.SerializerSettings.PreserveReferencesHandling = Newtonsoft.Json.PreserveReferencesHandling.Objects;
config.Formatters.Remove(config.Formatters.XmlFormatter);

我传递的另一种方法是为每个调用创建一组全新的强类型模型。我不想这样做，因为我有很多东西要用于 WebAPI。

Answer 4

这是另一个可用于WinForms、WPF 或Console 应用的示例

客户端代码

async Task<CalendarView> GetData(int month, int year, int deviceTypeID)
        {
            var result = new MSOCommon.CalendarView();
            try
            {
                HttpClient client = new HttpClient();

                var calendarRequest = new CalendarRequest()
                {
                    Month = month,
                    Year = year,
                     DeviceTypeID = deviceTypeID,
                    UserInfo = Program.UserInfo
                };

                var url = Properties.Settings.Default.ServerBaseUrl + string.Format("/api/calendar/Calendar");

                HttpResponseMessage response = await client.PostAsync(url, calendarRequest.AsJson());
                if (response.IsSuccessStatusCode)    // Check the response StatusCode
                {
                    var serSettings = new JsonSerializerSettings()
                    {
                        TypeNameHandling = TypeNameHandling.All
                    };    

                    string responseBody = await response.Content.ReadAsStringAsync();

                    result = JsonConvert.DeserializeObject<MSOCommon.CalendarView>(responseBody, serSettings);
                }
                else
                {
                    logger.Error(Properties.Resources.DATACannotGetCalendar);
                }
            }
            catch (Exception ex)
            {
                logger.Error(Properties.Resources.DATACannotGetCalendar + " " + ex.Message);
                logger.Error(ex);
            }

            return result;
        }

控制器服务器端代码

 [HttpPost()]
        public CalendarView Calendar(CalendarRequest calendarRequest)
        {
            logger.Info(string.Format("Get calendar for month {0} and year {1} ", calendarRequest.Month, calendarRequest.Year));
            // TODO Check username
            var result = new CalendarView();

            using (var db = new MSOnlineEntities())
            {
                result =   db.Calendars.Include("CalendarDetails")
                     .Where(x => x.CMonth == calendarRequest.Month && x.CYear == calendarRequest.Year && x.CDeviceTypeID == calendarRequest.DeviceTypeID).ToList()
                     .ConvertAll(x => new CalendarView
                     {
                         ID = x.ID,
                         CMonth = x.CMonth,
                         CYear = x.CYear,
                         CDays = x.CDays,
                         CDeviceTypeID = x.CDeviceTypeID,
                         ClosedAtTime = x.ClosedAtTime,
                         ClosedByUser = x.ClosedByUser,
                         IsClosed = x.IsClosed,
                         CalendarDetails = x.CalendarDetails.ToList().ConvertAll(d => new CalendarDetailView
                         {
                             ID = d.ID,
                             CalendarID = d.CalendarID,
                             MachineID = d.MachineID,
                             MachineName = d.DATA_MACHINE.Name,
                             D1 = d.D1 ?? -1,
                             D2 = d.D2 ?? -1,
                             D3 = d.D3 ?? -1,
                             D4 = d.D4 ?? -1,
                             D5 = d.D5 ?? -1,
                             D6 = d.D6 ?? -1,
                             D7 = d.D7 ?? -1,
                             D8 = d.D8 ?? -1,
                             D9 = d.D9 ?? -1,
                             D10 = d.D10 ?? -1,
                             D11 = d.D11 ?? -1,
                             D12 = d.D12 ?? -1,
                             D13 = d.D13 ?? -1,
                             D14 = d.D14 ?? -1,
                             D15 = d.D15 ?? -1,
                             D16 = d.D16 ?? -1,
                             D17 = d.D17 ?? -1,
                             D18 = d.D18 ?? -1,
                             D19 = d.D19 ?? -1,
                             D20 = d.D20 ?? -1,
                             D21 = d.D21 ?? -1,
                             D22 = d.D22 ?? -1,
                             D23 = d.D23 ?? -1,
                             D24 = d.D24 ?? -1,
                             D25 = d.D25 ?? -1,
                             D26 = d.D26 ?? -1,
                             D27 = d.D27 ?? -1,
                             D28 = d.D28 ?? -1,
                             D29 = d.D29 ?? -1,
                             D30 = d.D30 ?? -1,
                             D31 = d.D31 ?? -1
                         })
                     }).FirstOrDefault();

                return result;
            }
        }

Answer 5

在服务器上使用[HttpGet] 而不是[HttpPost]

 HttpResponseMessage response = 
 await client.GetAsync(string.format("api/product?id={0}&type={1}",param.Id.Value,param.Id.Type);

我的答案和 NMK 接受的答案之间的区别是 ? 而不是 / 这对我有用