NetCore3.0实现自定义IOC容器注入

原文: NetCore3.0实现自定义IOC容器注入

在之前的ASP.NET MVC实现依赖注入一文中，通过替换默认的ControllerFactory来达到对Controller生命周期的拦截，实现自定义的对象注入，在NetCore3.0中需要重新实现，步骤如下：

1.获取所有相关业务程序集

public static List GetFrameworkAssemblys()
      {
          var list = new List();
          var deps = DependencyContext.Default;
          var libs = deps.CompileLibraries;
          foreach ( var lib in libs)
          {
              if (!lib.Serviceable && lib.Type != "package" && lib.Name.StartsWith( "FastCloud" ))
              {
                  var assembly = AssemblyLoadContext.Default.LoadFromAssemblyName( new AssemblyName(lib.Name));
                  list.Add(assembly);
              }
          }
          return list;
      }

2.对所有Component组件注册

public class InjectContext
    {
        private static ContainerBuilder Container;
        public static void Init()
        {
            InjectFrameWork();
        }

        public static void InjectFrameWork()
        {
            Container = new ContainerBuilder();
            //获框架取所有程序集
            List assemblies = CloudUtil.GetFrameworkAssemblys();
            //注入框架所有Component组件
            Container.RegisterAssemblyTypes(assemblies.ToArray(), typeof (Component), true );
            Container.Build(CotainerEnum.BuidlModel.OverWrite);
        }

        public static object Resolve(Type Type, CotainerEnum.TypeEqual TypeEqual = CotainerEnum.TypeEqual.Ref)
        {
            return Container.Resolve(Type, TypeEqual);
        }

        public static List GetRegistType(Type @Type)
        {
            return Container.GetRegistType(@Type);
        }
    }

3.实现自定义Controller工厂

public class CloudControllerActivator : IControllerActivator
    {
        public object Create(ControllerContext context)
        {
            if (context == null )
            {
                throw new ArgumentNullException(nameof(context));
            }

            if (context.ActionDescriptor == null )
            {
                throw new ArgumentException(nameof(ControllerContext.ActionDescriptor));
            }

            var controllerTypeInfo = context.ActionDescriptor.ControllerTypeInfo;

            if (controllerTypeInfo == null )
            {
                throw new ArgumentException(nameof(context.ActionDescriptor.ControllerTypeInfo));
            }

            Type controllerType = controllerTypeInfo.AsType();
            return InjectContext.Resolve(controllerType);
        }

        public void Release(ControllerContext context, object controller)
        {
            if (context == null )
            {
                throw new ArgumentNullException(nameof(context));
            }

            if (controller == null )
            {
                throw new ArgumentNullException(nameof(controller));
            }

            var disposable = controller as IDisposable;
            if (disposable != null )
            {
                disposable.Dispose();
            }

        }
    }

4.修改配置，使用自定义Controller工厂

//替换默认Controller工厂
var defaultActivator = services.FirstOrDefault(c => c.ServiceType == typeof (IControllerActivator));
if (defaultActivator != null )
{
    services.Remove(defaultActivator);
}
services.AddSingleton();