Question

在ApsNetCore RC2网络应用程序中，我在注入IHttpContextAccessor时出现问题

我有一个实现IHttpContextAccessor的类HttpContextService，在stratup.cs中我添加了它services.AddTransient<IHttpContextAccessor, HttpContextService>();

当我运行项目时它停止而没有显示错误，所以我查看了日志并发现了这个：的＆＃39; dotnet.exe＆＃39; （CoreCLR：clrhost）：已加载＆＃39; C：\ Program Files \ dotnet \ shared \ Microsoft.NETCore.App \ 1.0.0-rc2-3002702 \ System.Net.Primitives.dll＆＃39;。无法找到或打开PDB文件。抛出异常：＆＃39; System.IO.FileNotFoundException＆＃39;在mscorlib.ni.dll中抛出异常：＆＃39; System.IO.FileNotFoundException＆＃39;在mscorlib.ni.dll中抛出异常：＆＃39; System.InvalidOperationException＆＃39;在Microsoft.Extensions.DependencyInjection.dll

中

是否有人有相同的问题或解决方案来修复它？

编辑：我尝试以两种方式激活服务：

    //this one throws and error Unable to resolve service for type 'Microsoft.AspNetCore.Http.IHttpContextAccessor' while attempting to activate 'EPTV.Services.HttpContextService'.
        services.AddTransient<HttpContextService>();
//and with this one the project dont even start like I explained before
        services.AddTransient<IHttpContextAccessor, HttpContextService>();

服务如下：

public class HttpContextService : IHttpContextAccessor
    {
        private readonly IHttpContextAccessor _accessor;

        public HttpContext HttpContext
        {
            get { return HttpContext; }

            set { HttpContext = value; }
        }

        public HttpContextService(IHttpContextAccessor accessor)
        {
            _accessor = accessor;
        }

        public HttpContext GetHttpContext()
        {
            return _accessor.HttpContext;
        }
        public string GetHeader(string value)
        {
            return _accessor.HttpContext.Request.Headers[value];
        }

        public string GetUserAgent()
        {
            return _accessor.HttpContext.Request.Headers["User-Agent"];
        }

        public string GetHost()
        {
            return _accessor.HttpContext.Request.Host.Value;
        }
    }

这是我得到的例外：

抛出异常：＆＃39; System.InvalidOperationException＆＃39;在Microsoft.Extensions.DependencyInjection.dll中附加信息：检测到类型为＆＃39; Microsoft.AspNetCore.Http.IHttpContextAccessor＆＃39;的服务的循环依赖关系。

Answer 1

您需要添加＆＃34; System.Net.Primitives＆＃34;在project.json的依赖项中。

"dependencies": {
    "Microsoft.NETCore.App": {
      "type": "platform",
      "version": "1.0.0-rc2-3002702"
    },
    "System.Net.Primitives": "4.0.11-rc2-24027"
  }

Answer 2

不支持修改ASP.NET Core服务，请参阅this Github issue进行讨论。

here

描述了您的问题的“hacky”解决方案

Answer 3

我终于找到了解决方案。

似乎在AspNetCore rc2中你必须在startup.cs中注册IHttpContextAccessor services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();

然后你就可以在控制器或其他服务中注入IHttpContextAccessor

System.Net.Primitives.dll找不到该文件

3 个答案: