NET MVC，循环中的异步任务

Question

我是新的异步编程在asp中，我有一个问题和问题。我想连接到外部API和我创建类任务，这里是类的一个znippet

public class Tasks 
{ 
    HttpClient httpc = new HttpClient(); 

    public async System.Threading.Tasks.Task<String> getStations() 
    { 
     var uri = new Uri("http://api.gios.gov.pl/pjp-api/rest/station/findAll"); 
     var response = await httpc.GetAsync(uri); 
     return await response.Content.ReadAsStringAsync(); 
    } 

    public async System.Threading.Tasks.Task<String> getStationDetails(int id) 
    { 
     string path = "http://api.gios.gov.pl/pjp-api/rest/station/sensors/" + id; 
     var uri = new Uri(path); 
     var response = await httpc.GetAsync(uri); 
     return await response.Content.ReadAsStringAsync(); 
    } 

    public async System.Threading.Tasks.Task<String> getStationValues(int id) 
    { 
     string path = "http://api.gios.gov.pl/pjp-api/rest/data/getData/" + id; 
     var uri = new Uri(path); 
     var response = await httpc.GetAsync(uri); 
     return await response.Content.ReadAsStringAsync(); 
    } 

然后我为我的请求，其中，i准备数据以响应

 public async Task<ActionResult> prepareAirContitionData(int id) 
    { 
     Task<string> taskStationDetails = tasks.getStationDetails(id); 
     string stationDetail = await taskStationDetails; 

     List<Station> stationsObj = JsonConvert.DeserializeObject<List<Station>>(stationDetail); 

     List<Task<string>> stationsValues = new List<Task<string>>(); 
     foreach(var station in stationsObj) 
     { 
      stationsValues.Add(tasks.getStationValues(station.stationId)); 
     } 

     string[] war = await Task.WhenAll(stationsValues.ToArray()); 
     Console.Write(war); 
     return Json("", JsonRequestBehavior.AllowGet); 
    } 

创建asyncronous控制器这是我的任务草案。问题出现在循环中，当我收集任务并等待它时，它们不显示在我的字符串数组中，只填充一个变量。

Answer 1

看样子你打了同样的问题，因为这等SO question

你需要传回所提取的响应