Question

我在Global.asax.cs中的session_start中重构我的ASP MVC代码，并对外部服务进行异步调用。我要么在IE中获得一个无限旋转的白页，要么执行立即返回到调用线程。在Session_start（）中，当我尝试.Result时，我得到了带有旋转IE图标的白页。当我尝试.ContinueWith（）时，执行返回到下一行，这取决于异步的结果。因此，authResult始终为null。有人可以帮忙吗？感谢。

这是来自Session_Start（）

         if (Session["userProfile"] == null) {
           //call into an async method
           //authResult = uc.checkUserViaWebApi(networkLogin[userLoginIdx]).Result;
           var userProfileTask = uc.checkUserViaWebApi(networkLogin[userLoginIdx])
             .ContinueWith(result => {
               if (result.IsCompleted) {
                 authResult = result.Result;
               }
             });

           Task.WhenAll(userProfileTask);

           if (authResult.Result == enumAuthenticationResult.Authorized) {

这是来自User_Controller类

   public async Task < AuthResult > checkUserViaWebApi(string networkName) {
       UserProfile _thisProfile = await VhaHelpersLib.WebApiBroker.Get < UserProfile > (
         System.Configuration.ConfigurationManager.AppSettings["userWebApiEndpoint"], "User/Profile/" + networkName);


       AuthResult authenticationResult = new AuthResult();

       if (_thisProfile == null) /*no user profile*/ {
         authenticationResult.Result = enumAuthenticationResult.NoLSV;
         authenticationResult.Controller = "AccessRequest";
         authenticationResult.Action = "LSVInstruction";
       }

这是使用HttpClient进行实际调用的助手类

 public static async Task<T> Get<T>(string baseUrl, string urlSegment)
    {
      string content = string.Empty;
      using(HttpClient client = GetClient(baseUrl))
      {

        HttpResponseMessage response = await client.GetAsync(urlSegment.TrimStart('/')).ConfigureAwait(false);
        if(response.IsSuccessStatusCode)
        {
          content = await response.Content.ReadAsStringAsync();

        }
        return JsonConvert.DeserializeObject<T>(content);
      }

Answer 1

It doesn't make sense to call User_Controller from Session_Start.

You want to call VhaHelpersLib directly inside Session_Start, if VhaHelpersLib doesn't have any dependencies.

Since Session_Start is not async, you want to use Result.

var setting = ConfigurationManager.AppSettings["userWebApiEndpoint"];
 UserProfile profile = await VhaHelpersLib.WebApiBroker.Get<UserProfile>(
        setting, "User/Profile/" + networkName).Result;

if (profile == enumAuthenticationResult.Authorized) {
  ...
}

async得不到哪里

1 个答案: