'HttpContext' class 怎么用？

Question

我在使用 HttpContext class 时遇到问题。我可以访问 HttpContext 但不能调用它的函数。

我想在助手中使用 HttpContext.Authentication class 我正在写。

我不能在我的助手中写这样的东西（见下文）class：

private void SignInUser()
{
... Code
await HttpContext.Authentication.SignInAsync(..);
}

但是，我可以在我的控制器中访问 HttpContext class。

如果有任何帮助，我将不胜感激。提前致谢。

Answer 1

首先创建文件HttpContext.cs

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;

namespace System.Web
{
    public static class HttpContext
    {
        private static IHttpContextAccessor _contextAccessor;

        public static Microsoft.AspNetCore.Http.HttpContext Current => _contextAccessor.HttpContext;

        internal static void Configure(IHttpContextAccessor contextAccessor)
        {
            _contextAccessor = contextAccessor;
        }
    }

    public static class StaticHttpContextExtensions
    {
        public static void AddHttpContextAccessor(this IServiceCollection services)
        {
            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
        }

        public static IApplicationBuilder UseStaticHttpContext(this IApplicationBuilder app)
        {
            var httpContextAccessor = app.ApplicationServices.GetRequiredService<IHttpContextAccessor>();
            System.Web.HttpContext.Configure(httpContextAccessor);
            return app;
        }
    }
}

启动文件中的下一个

public void ConfigureServices(IServiceCollection services)
...
 services.AddTransient<IHttpContextAccessor, HttpContextAccessor>();
 services.AddHttpContextAccessor();
...

最后例如在控制器之外，如果您需要当前用户名

var currentUsername = !string.IsNullOrEmpty(System.Web.HttpContext.Current?.User?.Identity?.Name)
            ? System.Web.HttpContext.Current.User.Identity.Name
            : "Anonymous";

我测试了 ASPNET Core 1.0 和 1.1

编辑抱歉，我忘记在配置部分的启动文件中添加：

public void Configure(IApplicationBuilder app)
...
app.UseStaticHttpContext();
...

Answer 2

如果您想使用一个帮助程序 class 来登录用户，您应该创建一个扩展方法，它可以环绕 IHttpContextAccessor 或 HttpContext 本身。

public static class HttpContextExtensions 
{
    public static void SignInUser(this HttpContext context)
    {
        await context.Authentication.SignInAsync(..);
    }

    public static void SignInUser(this.IHttpContextAccessor contextAccessor) 
    {
        // Calls the method from above
        contextAccessor.HttpContext.SignInUser();
    }
}

或者，如果您有更大的依赖链并需要其他注入服务，请将其转换为可注入服务 class：

public class UserLogonService : IUserLogonService 
{
    private readonly IHttpContextAccessor contextAccessor;

    public UserLogonService(IHttpContextAccessor contextAccessor)
    {
        if(contextAccessor==null)
            throw new ArgumentNullException(nameof(contextAccessor));

        this.contextAccessor = contextAccessor;
    }

    public void SingInUser()
    {
        contextAccessor.HttpContext.SignInUser();
    }
}

在Startup.Configure方法中：

services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
services.AddSingleton<IUserLogonService, UserLogonService>();

现在您可以通过构造函数在项目的任何地方注入 IUserLogonService，即

public class MyController
{
    private readonly IUserLogonService userLogon;

    public MyController(IUserLoggonService userLogon)
    {
        this.userLogon = userLogon;
    }

    public async Task<IActionResult> Login()
    {
        await userLogon.SignInUser();
    }
}

它干净、解耦并且可以轻松进行单元测试，这是静态助手无法做到的 class。

'HttpContext' class 怎么用？

How do you use 'HttpContext' class?

httpcontext

asp.net-core