.Net Core System.Net.Http.HttpRequestException使用angularjs模板開始一個新項目時的異常

Question

我試圖用.Net Core的SPA模板創建一個角度爲2的應用程序。要安裝模板，我用命令

dotnet new --install Microsoft.AspNetCore.SpaTemplates::* 

一旦安裝完成後，我跑

dotnet new angular 

創建一個新的AngularJS項目給我。我使用.csproj文件在Visual Studio 2017 Community Edition中打開了新項目。然後我運行該應用程序而無需調試（Ctrl + F5）。
我有以下錯誤

System.AggregateException: One or more errors occurred. (An error occurred while sending the request.) ---> System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.Http.WinHttpException: A connection with the server could not be established 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult() 
    at System.Net.Http.WinHttpHandler.<StartRequest>d__105.MoveNext() 
    --- End of inner exception stack trace --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult() 
    at System.Net.Http.HttpClient.<FinishSendAsync>d__58.MoveNext() 
--- End of stack trace from previous location where exception was thrown --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at Microsoft.AspNetCore.NodeServices.HostingModels.HttpNodeInstance.<InvokeExportAsync>d__7`1.MoveNext() 
--- End of stack trace from previous location where exception was thrown --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at Microsoft.AspNetCore.NodeServices.HostingModels.OutOfProcessNodeInstance.<InvokeExportAsync>d__14`1.MoveNext() 
--- End of stack trace from previous location where exception was thrown --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at Microsoft.AspNetCore.NodeServices.NodeServicesImpl.<InvokeExportWithPossibleRetryAsync>d__10`1.MoveNext() 
    --- End of inner exception stack trace --- 
    at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions) 
    at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification) 
    at Microsoft.AspNetCore.Builder.WebpackDevMiddleware.UseWebpackDevMiddleware(IApplicationBuilder appBuilder, WebpackDevMiddlewareOptions options) 
    at Sample.Startup.Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory) in C:\DotNetCore\Sample\Startup.cs:line 44 
--- End of stack trace from previous location where exception was thrown --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at Microsoft.AspNetCore.Hosting.ConventionBasedStartup.Configure(IApplicationBuilder app) 
    at Microsoft.AspNetCore.Hosting.Internal.WebHost.BuildApplication() 
---> (Inner Exception #0) System.Net.Http.HttpRequestException: An error occurred while sending the request. ---> System.Net.Http.WinHttpException: A connection with the server could not be established 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult() 
    at System.Net.Http.WinHttpHandler.<StartRequest>d__105.MoveNext() 
    --- End of inner exception stack trace --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1.ConfiguredTaskAwaiter.GetResult() 
    at System.Net.Http.HttpClient.<FinishSendAsync>d__58.MoveNext() 
--- End of stack trace from previous location where exception was thrown --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at Microsoft.AspNetCore.NodeServices.HostingModels.HttpNodeInstance.<InvokeExportAsync>d__7`1.MoveNext() 
--- End of stack trace from previous location where exception was thrown --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at Microsoft.AspNetCore.NodeServices.HostingModels.OutOfProcessNodeInstance.<InvokeExportAsync>d__14`1.MoveNext() 
--- End of stack trace from previous location where exception was thrown --- 
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) 
    at Microsoft.AspNetCore.NodeServices.NodeServicesImpl.<InvokeExportWithPossibleRetryAsync>d__10`1.MoveNext()<--- 

有人可以幫我想出解決辦法？我試圖讓一個簡單的Hello World應用程序工作，但我堅持這一點。

Answer 1

根據異常的初始來源：

Microsoft.AspNetCore.NodeServices.NodeServicesImpl.<InvokeExportWithPossibleRetryAsync>d__10`1.MoveNext()<--- 

看起來你沒有node正在啓動或正常工作要做。它試圖用InvokeExportWithPossibleRetryAsync做一些事情，所以它可能是一個啓動問題。你有沒有檢查你的node狀態？可能需要重新啓動。