如何使用 Autofac 注入 AutoMapper？

Question

将AutoMapper注入其他层的正确方法是什么？

我读了这个博客post，但是这段代码导致下面的异常

An exception of type 'AutoMapper.AutoMapperMappingException' occurred in AutoMapper.dll but was not handled in user code

在服务层尝试映射时。

List<StudentViewModel> list2 = _mapper.Map<List<StudentViewModel>>(list);

我的 AutoFac 配置如下：

public static class DependencyRegistration
{
    public static void Config()
    {
        var builder = new ContainerBuilder();

        builder.RegisterControllers(typeof(MvcApplication).Assembly);


        builder.RegisterType<TypeMapFactory>().As<ITypeMapFactory>();
        builder.RegisterType<ConfigurationStore>().As<ConfigurationStore>().WithParameter("mappers", MapperRegistry.Mappers).SingleInstance();
        builder.Register((ctx, t) => ctx.Resolve<ConfigurationStore>()).As<IConfiguration>().As<IConfigurationProvider>();
        builder.RegisterType<MappingEngine>().As<IMappingEngine>();

        //...
        var container = builder.Build();
        DependencyResolver.SetResolver(new AutofacDependencyResolver(container));
    }
}

Answer 1

看来您需要使用在容器中注册的 IConfiguration 对象来创建这样的地图：

var configuration = container.Resolve<IConfiguration>();
configuration.CreateMap<Student, StudentViewModel>();

我认为您应该在申请开始时就这样做。

这是在 Config 方法中配置事物的更好方法 (IMO)：

public static void Config()
{
    var configuration_store = new ConfigurationStore(new TypeMapFactory(), MapperRegistry.Mappers);

    var mapping_engine = new MappingEngine(configuration_store);

    configuration_store.CreateMap<Student, StudentViewModel>();

    var builder = new ContainerBuilder();

    builder.RegisterInstance(mapping_engine).As<IMappingEngine>();

    //...
    var container = builder.Build();
    DependencyResolver.SetResolver(new AutofacDependencyResolver(container));
}

我假设在最后一个示例中，您的类只需要访问 IMappingEngine（而不是 IConfiguration），因为您应该已经在 Config 方法（或应用程序启动时的其他一些配置方法）。

Answer 2

.netcore 3 Autofac 5.1.2 AutoMapper 9.0.0 AutoMapperProfiles -> 我的配置文件名称

protected override void Load(ContainerBuilder builder)
{
    builder.RegisterType<AutoMapperProfiles>().As<Profile>();
    builder.Register(c => new MapperConfiguration(cfg =>
    {
        foreach (var profile in c.Resolve<IEnumerable<Profile>>())
        {
            cfg.AddProfile(profile);
        }
    })).AsSelf().SingleInstance();

    builder.Register(c => c.Resolve<MapperConfiguration>().CreateMapper(c.Resolve)).As<IMapper>().InstancePerLifetimeScope();
}

如何使用 Autofac 注入 AutoMapper？

How to inject AutoMapper with Autofac?

c#

asp.net-mvc

dependency-injection

autofac

automapper