无法在 Web Api 项目中配置 autofac

Question

我遇到了一个奇怪的问题，这两天一直让我很困惑。由于我已经研究并尝试了不同的解决方案，因此尚未解决。

Autofac 用作 DI 容器。该解决方案包含多个项目，包括 ASP.NET MVC 5 和 Web API。我们无法在 API 项目中配置和注册 Autofac，而它在 Web 项目上正常工作。

我已经尝试了多种解决方案，例如下面的链接，但其中 none 有效。

...

我遇到了错误“ 尝试创建 'OperationController' 类型的控制器时出错。确保控制器具有无参数 public 构造函数".

代码如下

Startup.cs

public void Configuration(IAppBuilder app)
        {
            var httpConfig = new HttpConfiguration();

            ConfigureOAuth(app);

            WebApiConfig.Register(httpConfig);
            app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);

            RegisterMappers();

            var builder = new ContainerBuilder();
            //builder.RegisterApiControllers(Assembly.GetExecutingAssembly()).PropertiesAutowired();
            builder.RegisterApiControllers(typeof(OperationController).Assembly).PropertiesAutowired();

            builder.RegisterAssemblyTypes(Assembly.Load("PSMS.Repository"))
                .Where(t => t.Name.EndsWith("Repository"))
                .AsImplementedInterfaces()
                .InstancePerLifetimeScope();

            builder.RegisterType<PsmsDbContext>().InstancePerRequest();
            builder.RegisterType<TransactionDbContext>().InstancePerRequest();
            builder.RegisterGeneric(typeof(UnitOfWork<>)).As(typeof(IUnitOfWork<>)).InstancePerDependency();

            var container = builder.Build();
            DependencyResolver.SetResolver(new AutofacDependencyResolver(container));
            GlobalConfiguration.Configuration.DependencyResolver = new AutofacWebApiDependencyResolver(container);

            app.UseWebApi(httpConfig);
        }

OperationController.cs

[RoutePrefix("api/Operation")]
public class OperationController : ApiController
{
    private readonly IUserRepository _userRepository;
    private readonly ITerminalsRepository _terminalsRepository;
    private readonly ITaskHeaderRepository _taskHeaderRepository;

    public OperationController(
        IUserRepository userRepository,
        ITerminalsRepository terminalsRepository,
        ITaskHeaderRepository taskHeaderRepository)
    {
        _userRepository = userRepository;
        _terminalsRepository = terminalsRepository;
        _taskHeaderRepository = taskHeaderRepository;
    }

[Authorize]
    [Route("~/api/Operation/FindTerminal")]
    [HttpPost]
    public IHttpActionResult FindTerminal(GetTerminalInputDto inputDto)
    {
        if (string.IsNullOrEmpty(inputDto.TerminalNo))
            return ResponseMessage(new HttpResponseMessage(HttpStatusCode.NotAcceptable));

        var userPersonnel = _userRepository.GetPersonnelUser(inputDto.TerminalNo);

        var terminal = _terminalsRepository.SearchTerminals(new TerminalsSearchContext
        {
            Terminal = new Terminals
            {
                TerminalNo = inputDto.TerminalNo
            },
            PersonnelId = userPersonnel.PersonnelId ?? 0,
            PersonnelType = (Enumeration.PersonnelTypeEnum)userPersonnel.PersonnelTypeId,
            Take = 1,
            Skip = 0
        }).FirstOrDefault();

        var result = new GetTerminalOutputDto(terminal);
        return Json(result);
    }
}

我再次重复，相同的配置在 ASP.NET MVC 项目中有效。感谢任何帮助

Answer 1

您使用的是 OWIN，而不是经典 Web API 设置。 Per the docs:

A common error in OWIN integration is use of the GlobalConfiguration.Configuration. In OWIN you create the configuration from scratch. You should not reference GlobalConfiguration.Configuration anywhere when using the OWIN integration.

切换这个：

GlobalConfiguration.Configuration.DependencyResolver = new AutofacWebApiDependencyResolver(container);

到

httpConfig.DependencyResolver = new AutofacWebApiDependencyResolver(container);

另外，不确定您为什么要设置 MVC 依赖解析器。对于 Web API，您不需要：

DependencyResolver.SetResolver(new AutofacDependencyResolver(container));

无法在 Web Api 项目中配置 autofac

Unable to configure autofac in Web Api project

c#

dependency-injection

autofac

asp.net-web-api

asp.net-mvc-5