Autofac学习之三种生命周期：InstancePerLifetimeScope、SingleInstance、InstancePerDependency

InstancePerLifetimeScope：同一个Lifetime生成的对象是同一个实例

SingleInstance：单例模式，每次调用，都会使用同一个实例化的对象；每次都用同一个对象；

InstancePerDependency：默认模式，每次调用，都会重新实例化对象；每次请求都创建一个新的对象；

验证方法实现逻辑：在类的构造函数中，给属性赋值（GUID），通过判断属性值是否一致来判断 三种生命周期的效果。

先上图看结果：

1、InstancePerLifetimeScope

2、SingleInstance

3、InstancePerDependency

整块代码实现如下：

using Autofac;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;

namespace SimpleAutofacConsole
{
    class Program
    {
        static void Main(string[] args)
        {
            //IAnimal animal = new Tiger();
            //animal.Show("普通new()对象");

            var builder = new ContainerBuilder();
            var dependencyRegistrar = new DependencyRegistrar();//(IDependencyRegistrar)Activator.CreateInstance(typeof(IDependencyRegistrar));
            dependencyRegistrar.Register(builder, null);

            var container = builder.Build();

            var animalIOC = container.Resolve<IAnimal>();
            //animalIOC.Show("Autofac方式实现new()对象");
            Console.WriteLine(animalIOC.Id);

            var animalIOC2 = container.Resolve<IAnimal>();
            //animalIOC2.Show("第二次从容器中实例化");
            Console.WriteLine(animalIOC2.Id);

            Console.WriteLine("开启新的生命周期");
            ILifetimeScope inner = container.BeginLifetimeScope();
            var myClass3 = inner.Resolve<IAnimal>();
            Console.WriteLine(myClass3.Id);
            var myClass4 = inner.Resolve<IAnimal>();
            Console.WriteLine(myClass4.Id);

            //var animalIOC = container.Resolve<Dog>();
            //animalIOC.Show("Autofac方式实现new()对象");

            Console.ReadLine();
        }
    }
    public interface IAnimal
    {
        void Show(string name);
        string Id { get; set; }
    }
    public class Tiger : IAnimal
    {
        private string _Id;
        public string Id { get { return this._Id; } set { Id = this._Id; } }
        public Tiger()
        {
            _Id = Guid.NewGuid().ToString();
        }

        public void Show(string name)
        {
            Console.WriteLine("老虎说：" + name);
        }
    }
    public class Dog : IAnimal
    {
        public string Id { get { return Guid.NewGuid().ToString(); } set { } }

        public void Show(string name)
        {
            Console.WriteLine("狗狗说：" + name);
        }
    }
    public class DependencyRegistrar : IDependencyRegistrar
    {
        public int Order { get { return 0; } }

        public void Register(ContainerBuilder builder, ITypeFinder typeFinder)
        {
            // InstancePerLifetimeScope 同一个Lifetime生成的对象是同一个实例
            // SingleInstance 单例模式，每次调用，都会使用同一个实例化的对象；每次都用同一个对象
            // InstancePerDependency 默认模式，每次调用，都会重新实例化对象；每次请求都创建一个新的对象
            builder.RegisterType<Tiger>().As<IAnimal>().InstancePerLifetimeScope();
            //builder.RegisterType<Dog>().As<IAnimal>();//.PreserveExistingDefaults();
        }
    }

    public interface IDependencyRegistrar
    {
        void Register(ContainerBuilder builder,ITypeFinder typeFinder);

        int Order { get; }
    }

    public interface ITypeFinder
    {
        IList<Assembly> GetAssemblies();

        IEnumerable<Type> FindClassesOfType(Type assignTypeFrom, bool onlyConcreteClasses = true);

        IEnumerable<Type> FindClassesOfType(Type assignTypeFrom, IEnumerable<Assembly> assemblies, bool onlyConcreteClasses = true);

        IEnumerable<Type> FindClassesOfType<T>(bool onlyConcreteClasses = true);

        IEnumerable<Type> FindClassesOfType<T>(IEnumerable<Assembly> assemblies, bool onlyConcreteClasses = true);
    }
}