C# Autofac未解析ApicController的类型和命名参数

我有三个不同的应用程序，它们都使用相同的业务层/数据层构建。我正在向所有三个应用程序都使用的IUnitOfWork类添加一个IUserNameProvider。因为每个应用程序使用不同的方法获取用户名，所以我创建了IUserNameProvider，并使用Autofac注入适当的实现

这似乎应该是相当简单的代码，但我无法为Web API应用程序正确配置它。类似的代码在控制台应用程序中运行良好

My Global.asax.cs

protected void Application_Start()
{
    var builder = new ContainerBuilder();

    builder.RegisterType<WebAPIGetUser>().As<SSEMPA.DataAccess.Infrastructure.IUserNameProvider>();
    builder.RegisterType<UnitOfWork>().As<IUnitOfWork>()
     .WithParameter("connectionString", ConfigurationManager.ConnectionStrings["MyDataContex"].ConnectionString);

    //other type registrations ...

    DependencyResolver.SetResolver(new AutofacDependencyResolver(builder.Build()));

    // other registrations ....
}

我的遥控器

public class AgencyApiController : ApiController
{
    private readonly IUnitOfWork _unitOfWork;

    public AgencyApiController(IUnitOfWork unitOfWork)
    {
        _unitOfWork = unitOfWork;
    }

    ...
}

当API被命中时，它会抛出以下错误：

<Error>
    <Message>An error has occurred.</Message>
    <ExceptionMessage>An error occurred when trying to create a controller of type 'AgencyApiController'. Make sure that the controller has a parameterless public constructor.
    </ExceptionMessage>
    <ExceptionType>System.InvalidOperationException</ExceptionType>
    <StackTrace>at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType) at System.Web.Http.Controllers.HttpControllerDescriptor.CreateController(HttpRequestMessage request) at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()
    </StackTrace>
    <InnerException>
        <Message>An error has occurred.</Message>
        <ExceptionMessage>None of the constructors found with 'Autofac.Core.Activators.Reflection.DefaultConstructorFinder' on type 'SSEMPA.DataAccess.Infrastructure.UnitOfWork' can be invoked with the available services and parameters: Cannot resolve parameter 'SSEMPA.DataAccess.Infrastructure.IUserNameProvider userNameProvider' of constructor 'Void .ctor(SSEMPA.DataAccess.Infrastructure.IUserNameProvider , System.String)'.
        </ExceptionMessage>
        <ExceptionType>Autofac.Core.DependencyResolutionException</ExceptionType>

发生了一个错误。
尝试创建“AgencyApicController”类型的控制器时出错。确保控制器具有无参数公共构造函数。
System.InvalidOperationException异常
位于System.Web.Http.controllerDescriptor.HttpControllerDescriptor.CreateController（HttpRequestMessage请求，HttpControllerDescriptor，controllerDescriptor类型），位于System.Web.Http.Dispatcher.HttpControllerDescriptor.CreateController（HttpRequestMessage请求），位于System.Web.Http.Dispatcher.HttpControllerDispatcher.d_u1.MoveNext（）
发生了一个错误。
在类型“SSEMPA.DataAccess.Infrastructure.UnitOfWork”上找到的具有“Autofac.Core.Activators.Reflection.DefaultConstructorFinder”的构造函数均不能使用可用服务和参数调用：无法解析构造函数“Void.ctor”的参数“SSEMPA.DataAccess.Infrastructure.IUserNameProvider userNameProvider”（SSEMPA.DataAccess.Infrastructure.IUserNameProvider，System.String）“”。
Autofac.Core.dependencResolutionException

我已经尝试为IUserNameProvider和connections字符串使用命名参数，但这并没有改变任何东西。看起来这应该可以工作，所以我肯定缺少一些小的东西

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感谢您查看此信息。

除了控制台应用程序之外，您还需要对WebAPI进行其他配置和设置。请查看此处的文档以获取说明：

谢谢！其他人配置了此功能，并且不再在项目中。我不知道已经内置了另一个配置。answ是什么呃，这会导致一个有100个链接的网站吗？？？为什么不在这里粘贴google.com呢？

<Error>
    <Message>An error has occurred.</Message>
    <ExceptionMessage>An error occurred when trying to create a controller of type 'AgencyApiController'. Make sure that the controller has a parameterless public constructor.
    </ExceptionMessage>
    <ExceptionType>System.InvalidOperationException</ExceptionType>
    <StackTrace>at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType) at System.Web.Http.Controllers.HttpControllerDescriptor.CreateController(HttpRequestMessage request) at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()
    </StackTrace>
    <InnerException>
        <Message>An error has occurred.</Message>
        <ExceptionMessage>None of the constructors found with 'Autofac.Core.Activators.Reflection.DefaultConstructorFinder' on type 'SSEMPA.DataAccess.Infrastructure.UnitOfWork' can be invoked with the available services and parameters: Cannot resolve parameter 'SSEMPA.DataAccess.Infrastructure.IUserNameProvider userNameProvider' of constructor 'Void .ctor(SSEMPA.DataAccess.Infrastructure.IUserNameProvider , System.String)'.
        </ExceptionMessage>
        <ExceptionType>Autofac.Core.DependencyResolutionException</ExceptionType>