IHttpContextAccessor is no longer wired up by default, you have to register it yourself

    services.TryAddSingleton&lt;IHttpContextAccessor, HttpContextAccessor&gt;();

As of .NET Core 2.1 there is an extension method that has been added to correctly register an `IHttpContextAccessor` as a singleton. See [Add helper to register IHttpContextAccessor #947][1]. Simply add as follows in your `ConfigureServices()` method:

    services.AddHttpContextAccessor();

This is equivalent to:

    services.TryAddSingleton&lt;IHttpContextAccessor, HttpContextAccessor&gt;();


  [1]: https://github.com/aspnet/HttpAbstractions/pull/947

    services.AddScoped(sp =&gt; sp.GetService&lt;IHttpContextAccessor&gt;().HttpContext.Session);

I&#39;m trying to create a module that exports multiple ES6 classes. Let&#39;s say I have the following directory structure:


    my/
    └── module/
        ├── Foo.js
        ├── Bar.js
        └── index.js

`Foo.js` and `Bar.js` each export a default ES6 class:

    // Foo.js
    export default class Foo {
      // class definition
    }

    // Bar.js
    export default class Bar {
      // class definition
    }

I currently have my `index.js` set up like this:

    import Foo from &#39;./Foo&#39;;
    import Bar from &#39;./Bar&#39;;
    
    export default {
      Foo,
      Bar,
    }

However, I am unable to import. I want to be able to do this, but the classes aren&#39;t found:

    import {Foo, Bar} from &#39;my/module&#39;;

What is the correct way to export multiple classes in an ES6 module?

Export multiple classes in ES6 modules

I am using Chart.js v2 to draw a simple line chart. Everything looks fine, except there are grid lines that I don&#39;t want:

[![Grid Lines I don&#39;t want][1]][1]


  [1]: http://i.stack.imgur.com/ir7Ll.jpg

The documentation for Line Chart is here: https://nnnick.github.io/Chart.js/docs-v2/#line-chart, but I can&#39;t find anything about hiding those &quot;Grid Lines&quot;.

How can I remove the grid lines?

Chart.js v2 - hiding grid lines

I started to convert my asp.net core RC1 project to RC2 and faced with problem that now `IHttpContextAccessor`does not resolved.

For sake of simplicity I created new ASP.NET RC2 project using Visual Studio Template `ASP.NET Core Web Application (.Net Framework)`. Than I added constructor for HomeController which template created for me.

    public HomeController(IHttpContextAccessor accessor)
    {
    }
And after I start application I receive next error:

&gt; InvalidOperationException: Unable to resolve service for type &#39;Microsoft.AspNetCore.Http.IHttpContextAccessor&#39; while attempting to activate &#39;TestNewCore.Controllers.HomeController&#39;.
в Microsoft.Extensions.Internal.ActivatorUtilities.GetService(IServiceProvider sp, Type type, Type requiredBy, Boolean isDefaultParameterRequired)

In my real application I need to resolve `IHttpContextAccessor` in my own service class for getting access to `_contextAccessor.HttpContext.Authentication` and to `_contextAccessor.HttpContext.User`. Everething works fine in RC1. So how can it suppose to be in RC2?

InvalidOperationException: Unable to resolve service for type &#39;Microsoft.AspNetCore.Http.IHttpContextAccessor&#39;

I started to convert my asp.net core RC1 project to RC2 and faced with problem that now <code>IHttpContextAccessor</code>does not resolved.
For sake of simplicity I created new ASP.NET RC2 project using Visual Studio Template <code>ASP.NET Core Web Application (.Net Framework)</code>. Than I added constructor for HomeController which template created for me.
<pre><code class="hljs language-arduino">public HomeController(IHttpContextAccessor accessor)
{
}
</code></pre>
And after I start application I receive next error:
> InvalidOperationException: Unable to resolve service for type 'Microsoft.AspNetCore.Http.IHttpContextAccessor' while attempting to activate 'TestNewCore.Controllers.HomeController'.
в Microsoft.Extensions.Internal.ActivatorUtilities.GetService(IServiceProvider sp, Type type, Type requiredBy, Boolean isDefaultParameterRequired)
In my real application I need to resolve <code>IHttpContextAccessor</code> in my own service class for getting access to <code>_contextAccessor.HttpContext.Authentication</code> and to <code>_contextAccessor.HttpContext.User</code>. Everething works fine in RC1. So how can it suppose to be in RC2?

Every time I build a project using the new .NET Core RC2 templates I am **not** provided with a runnable .**EXE** file. If I hit F5 for debugging my console application it runs fine through the 

    C:\Program Files\dotnet\dotnet.exe 
application. And if I use the 

    dotnet run 
command in the folder, it runs fine as well. But I see no way to run the application without the .NET Core CLI tools.

The contents of my 

     bin\Debug\netcoreapp1.0\
folder looks like this:

[![Bin folder structure][1]][1]


  [1]: http://i.stack.imgur.com/mbAkN.png

As you can see there is no .**EXE** file available. Just the dll.

Am I overlooking something? Or is there something wrong with my project.json file?

    {
      &quot;version&quot;: &quot;1.0.0-*&quot;,
      &quot;buildOptions&quot;: {
        &quot;emitEntryPoint&quot;: true
      },
    
      &quot;dependencies&quot;: {
        &quot;Microsoft.NETCore.App&quot;: {
          &quot;type&quot;: &quot;platform&quot;,
          &quot;version&quot;: &quot;1.0.0-rc2-3002702&quot;
        }
      },

      &quot;frameworks&quot;: {
        &quot;netcoreapp1.0&quot;: {
          &quot;imports&quot;: &quot;dnxcore50&quot;
        }
      }
    }

Thanks!




Build .exe file in .NET Core RC2

Time and time again, I see it said that using `async`-`await` doesn&#39;t create any additional threads. That doesn&#39;t make sense because the only ways that a computer can appear to be doing more than 1 thing at a time is

 - Actually doing more than 1 thing at a time (executing in parallel, making use of multiple processors)
 - Simulating it by scheduling tasks and switching between them (do a little bit of A, a little bit of B, a little bit of A, etc.)

So if `async`-`await` does neither of those, then how can it make an application responsive? If there is only 1 thread, then calling any method means waiting for the method to complete before doing anything else, and the methods inside that method have to wait for the result before proceeding, and so forth. 

If async-await doesn&#39;t create any additional threads, then how does it make applications responsive?

With the release of .NET Core RC2 Microsoft made it so there are now 3 Web Application templates:

- ASP.NET Web Application (.NET Framework) — The old
- ASP.NET Core Web Application (.NET Framework) — the new, to be hosting on Windows only
- ASP.NET Core Web Application (.NET Core) — Linux, OSX, Windows  

I am trying to use the new Core Web Application template but without trying to target Linux, OSX, Windows so it seems like the ASP.NET Core Web Application (.NET Framework) is perfect for me. It took me a while but I learned that in order to add a class library that will work with this project type you need to add a Class Library (.NET Core) and change the frameworks section to only be net461 to match the Web Application.

    &quot;frameworks&quot;: {
        &quot;net461&quot;: { }
    }

**My Question:**

What is the difference between creating an ASP.NET Core Web Application (.NET Core) and in project.json making net461 the only target framework 

and 

just creating an ASP.NET Core Web Application (.NET Framework) project which only includes net461 by default.

Are there other differences that I am not aware of like the way the projects are published, etc.?

Difference between using the ASP.NET Core Web Application (.NET Core) with net461 set as the only framework and using the (.NET Framework) template

I&#39;m having trouble uninstalling `Microsoft .NET Core 1.0.0 RC2 - VS 2015 Tooling Preview 1`.  I&#39;m in Windows 7, in the `Programs and Features` window.  When I click `uninstall`, it brings up a dialog box, with the options `repair`, `uninstall`, and `cancel`.  When I click `uninstall`, a &quot;Open file&quot; window pops up.

I&#39;ve googled a bit to see if there&#39;s a file I can download to sate this &quot;Open file&quot; window.  I can&#39;t find one anywhere.  Here are a few of the things I have looked at, but I can&#39;t make sense of which one may fit.

https://www.microsoft.com/net/download

The reason I&#39;m trying to uninstall this is because I&#39;m having a lot of trouble with Visual Studio 2015 community, and this is part of the troubleshooting process.

How do I uninstall &quot;Microsoft .NET Core 1.0.0 RC2 - VS 2015 Tooling Preview 1&quot;?

What is the difference between ASP.NET Core Web (.NET Core) vs ASP.NET Core Web (.NET Framework)?

and does .NET Framework provide [similar performance][1] as to .NET Core?

[1]: http://web.ageofascent.com/asp-net-core-exeeds-1-15-million-requests-12-6-gbps/

Difference between ASP.NET Core (.NET Core) and ASP.NET Core (.NET Framework)

I have a asp.net core application that uses dependency injection defined in the startup.cs class of the application:  

        public void ConfigureServices(IServiceCollection services)
        {

            services.AddDbContext&lt;ApplicationDbContext&gt;(options =&gt;
                options.UseSqlServer(Configuration[&quot;Data:FotballConnection:DefaultConnection&quot;]));


            // Repositories
            services.AddScoped&lt;IUserRepository, UserRepository&gt;();
            services.AddScoped&lt;IUserRoleRepository, UserRoleRepository&gt;();
            services.AddScoped&lt;IRoleRepository, RoleRepository&gt;();
            services.AddScoped&lt;ILoggingRepository, LoggingRepository&gt;();

            // Services
            services.AddScoped&lt;IMembershipService, MembershipService&gt;();
            services.AddScoped&lt;IEncryptionService, EncryptionService&gt;();

            // new repos
            services.AddScoped&lt;IMatchService, MatchService&gt;();
            services.AddScoped&lt;IMatchRepository, MatchRepository&gt;();
            services.AddScoped&lt;IMatchBetRepository, MatchBetRepository&gt;();
            services.AddScoped&lt;ITeamRepository, TeamRepository&gt;();

            services.AddScoped&lt;IFootballAPI, FootballAPIService&gt;();

This allows something like this: 

    [Route(&quot;api/[controller]&quot;)]
    public class MatchController : AuthorizedController
    {
        private readonly IMatchService _matchService;
        private readonly IMatchRepository _matchRepository;
        private readonly IMatchBetRepository _matchBetRepository;
        private readonly IUserRepository _userRepository;
        private readonly ILoggingRepository _loggingRepository;

        public MatchController(IMatchService matchService, IMatchRepository matchRepository, IMatchBetRepository matchBetRepository, ILoggingRepository loggingRepository, IUserRepository userRepository)
        {
            _matchService = matchService;
            _matchRepository = matchRepository;
            _matchBetRepository = matchBetRepository;
            _userRepository = userRepository;
            _loggingRepository = loggingRepository;
        }

This is very neat. But becomes a problem when I want to unit test. Because my test library does not have a startup.cs where I setup dependency injection. So a class with these interfaces as params will just be null. 

    namespace TestLibrary
    {
        public class FootballAPIService
        {
            private readonly IMatchRepository _matchRepository;
            private readonly ITeamRepository _teamRepository;
    
            public FootballAPIService(IMatchRepository matchRepository, ITeamRepository teamRepository)
    
            {
                _matchRepository = matchRepository;
                _teamRepository = teamRepository;

In the code above, in the test library, **_matchRepository** and **_teamRepository**, will just be **null**. :(

Can I do something like ConfigureServices, where I define dependency injection in my test library project?


how to unit test asp.net core application with constructor dependency injection

I need to be able to pass a connection string into some of my service implementations. I am doing this in the constructor. The connection string is configurable by user will be added the ClaimsPrincipal as a Claim.

All fine so far.

Unfortunately, I also want to be able to use the dependency injection features in ASP.NET Core to the fullest and resolve the service implementation though DI.

I have a POC implmentation: 

    public interface IRootService
    {
        INestedService NestedService { get; set; }

        void DoSomething();
    }

    public class RootService : IRootService
    {
        public INestedService NestedService { get; set; }

        public RootService(INestedService nestedService)
        {
            NestedService = nestedService;
        }

        public void DoSomething()
        {
            // implement
        }
    }


    public interface INestedService
    {
        string ConnectionString { get; set; }

        void DoSomethingElse();
    }

    public class NestedService : INestedService
    {
        public string ConnectionString { get; set; }

        public NestedService(string connectionString)
        {
            ConnectionString = connectionString;
        }

        public void DoSomethingElse()
        {
            // implement
        }
    }

These services have been registered during startup and `INestedService` has been added the constructor of a controller. 

    public HomeController(INestedService nestedService)
    {
        NestedService = nestedService;
    }

As expected, I get the error `Unable to resolve service for type &#39;System.String&#39; while attempting to activate &#39;Test.Dependency.Services.NestedService&#39;.`

What are my options here?

How can I pass a runtime parameter as part of the dependency resolution?

I&#39;ve built a basic app in Angular, but I have encountered a strange issue where I cannot inject a service into one of my components. It injects fine into any of the three other components I have created, however.

For starters, this is the service:

&lt;!-- language-all: lang-ts --&gt;

    import { Injectable } from &#39;@angular/core&#39;;
    
    @Injectable()
    export class MobileService {
      screenWidth: number;
      screenHeight: number;
    
      constructor() {
        this.screenWidth = window.outerWidth;
        this.screenHeight = window.outerHeight;
    
        window.addEventListener(&quot;resize&quot;, this.onWindowResize.bind(this) )
      }
      
      onWindowResize(ev: Event) {
        var win = (ev.currentTarget as Window);
        this.screenWidth = win.outerWidth;
        this.screenHeight = win.outerHeight;
      }
      
    }

And the component that it refuses to work with:

    import { Component, } from &#39;@angular/core&#39;;
    import { NgClass } from &#39;@angular/common&#39;;
    import { ROUTER_DIRECTIVES } from &#39;@angular/router&#39;;
    
    import {MobileService} from &#39;../&#39;;
    
    @Component({
      moduleId: module.id,
      selector: &#39;pm-header&#39;,
      templateUrl: &#39;header.component.html&#39;,
      styleUrls: [&#39;header.component.css&#39;],
      directives: [ROUTER_DIRECTIVES, NgClass],
    })
    export class HeaderComponent {
      mobileNav: boolean = false;
    
      constructor(public ms: MobileService) {
        console.log(ms);
      }
    
    }

The error I get in the browser console is this:

&gt; EXCEPTION: Can&#39;t resolve all parameters for HeaderComponent: (?).

I have the service in the bootstrap function so it has a provider. And I seem to be able to inject it into the constructor of any of my other components without issue.

Error when trying to inject a service into an angular component &quot;EXCEPTION: Can&#39;t resolve all parameters for component&quot;, why?

I am trying to port an ASP.NET application to ASP.NET Core. I have property injection (using Ninject) on my UnitOfWork implementation like this:

```c#
[Inject]
public IOrderRepository OrderRepository { get; set; }
[Inject]
public ICustomerRepository CustomerRepository { get; set; }
```

Is there a way to achieve the same functionality using built-in DI on .NET Core? Also, is it possible to use convention-based binding?

Property Injection in ASP.NET Core

If I wanted to use the annotation `@Qualifier` on a constructor dependency injection, I would have something like the following:

&lt;!-- language: java --&gt;

    public class Example {
	
        private final ComponentExample component;

        @Autowired
        public Example(@Qualifier(&quot;someComponent&quot;) ComponentExample component) {
            this.component = component;
        }
    }

I know Lombok&#39;s annotations to reduce boilerplate code and don&#39;t have to include a constructor would be as follows: `@RequiredArgsConstructors(onConstructor=@__(@Inject))` but this only works with properties without qualifiers. 

Anyone know if it is possible to add qualifiers in `@RequiredArgsConstructor(onConstructor = @__(@Autowired))`?

Is it possible to add qualifiers in @RequiredArgsConstructor(onConstructor = @__(@Autowired))?

Running my ASP.NET Core application using [DNX][1], I was able to set environment variables from the command line and then run it like this:

    set ASPNET_ENV = Production
    dnx web

Using the same approach in 1.0:

    set ASPNETCORE_ENVIRONMENT = Production
    dotnet run

does not work - the application does not seem to be able to read environment variables.

    Console.WriteLine(Environment.GetEnvironmentVariable(&quot;ASPNETCORE_ENVIRONMENT&quot;));
returns null

What am I missing?

  [1]: https://stackoverflow.com/questions/30374725/is-net-execution-environment-dnx-similar-to-mono




Read environment variables in ASP.NET Core

I want to add a processing time middleware to my ASP.NET Core WebApi like this

    public class ProcessingTimeMiddleware  
    {
        private readonly RequestDelegate _next;
    
        public ProcessingTimeMiddleware(RequestDelegate next)
        {
            _next = next;
        }
    
        public async Task Invoke(HttpContext context)
        {
            var watch = new Stopwatch();
            watch.Start();
    
            await _next(context);
    
            context.Response.Headers.Add(&quot;X-Processing-Time-Milliseconds&quot;, new[] { watch.ElapsedMilliseconds.ToString() });
        }
    }

But doing this throws an exception saying

     System.InvalidOperationException: Headers are readonly, reponse has already started.

How can I add headers to the response?