C# Autofac學習筆記_ZenDei技術網路在線

一、為什麼使用Autofac? Autofac是.NET領域最為流行的IoC框架之一，傳說是速度最快的一個。 1.1、性能有人專門做了測試： 1.2、優點 1）與C#語言聯繫很緊密。C#里的很多編程方式都可以為Autofac使用，例如可以使用Lambda表達式註冊組件。 2）較低的學習曲線。學習它 ...

一、為什麼使用Autofac?

Autofac是.NET領域最為流行的IoC框架之一，傳說是速度最快的一個。

1.1、性能

有人專門做了測試：

1.2、優點

1）與C#語言聯繫很緊密。C#里的很多編程方式都可以為Autofac使用，例如可以使用Lambda表達式註冊組件。

2）較低的學習曲線。學習它非常的簡單，只要你理解了IoC和DI的概念以及在何時需要使用它們。

3）支持JSON/XML配置。

4）自動裝配。

5）與Asp.Net MVC集成。

6）微軟的Orchad開源程式使用的就是Autofac，可以看出它的方便和強大。

1.3、資源

官方網站：http://autofac.org/

GitHub網址：https://github.com/autofac/Autofac

學習資料：Autofac中文文檔

二、數據準備

2.1、新建項目

IService下的介面類：

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

namespace LinkTo.Test.Autofac.IService
{
    /// <summary>
    /// 動物吠聲介面類
    /// </summary>
    public interface IAnimalBark
    {
        /// <summary>
        /// 吠叫
        /// </summary>
        void Bark();
    }
}

IAnimalBark

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

namespace LinkTo.Test.Autofac.IService
{
    /// <summary>
    /// 動物睡眠介面類
    /// </summary>
    public interface IAnimalSleep
    {
        /// <summary>
        /// 睡眠
        /// </summary>
        void Sleep();
    }
}

IAnimalSleep

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

namespace LinkTo.Test.Autofac.IService
{
    /// <summary>
    /// 學校介面類
    /// </summary>
    public interface ISchool
    {
        /// <summary>
        /// 放學
        /// </summary>
        void LeaveSchool();
    }
}

ISchool

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

namespace LinkTo.Test.Autofac.IService
{
    /// <summary>
    /// 學生介面類
    /// </summary>
    public interface IStudent
    {
        /// <summary>
        /// 增加學生
        /// </summary>
        /// <param name="studentID">學生ID</param>
        /// <param name="studentName">學生姓名</param>
        void Add(string studentID, string studentName);
    }
}

IStudent

Service下的介面實現類：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using LinkTo.Test.Autofac.IService;

namespace LinkTo.Test.Autofac.Service
{
    /// <summary>
    /// 貓類
    /// </summary>
    public class Cat : IAnimalSleep
    {
        /// <summary>
        /// 睡眠
        /// </summary>
        public void Sleep()
        {
            Console.WriteLine("小貓咪睡著了zZ");
        }
    }
}

Cat

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using LinkTo.Test.Autofac.IService;

namespace LinkTo.Test.Autofac.Service
{
    /// <summary>
    /// 狗類
    /// </summary>
    public class Dog : IAnimalBark, IAnimalSleep
    {
        /// <summary>
        /// 吠叫
        /// </summary>
        public void Bark()
        {
            Console.WriteLine("汪汪汪");
        }

        /// <summary>
        /// 睡眠
        /// </summary>
        public void Sleep()
        {
            Console.WriteLine("小狗狗睡著了zZ");
        }
    }
}

Dog

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using LinkTo.Test.Autofac.IService;

namespace LinkTo.Test.Autofac.Service
{
    /// <summary>
    /// 學校類
    /// </summary>
    public class School : ISchool
    {
        /// <summary>
        /// IAnimalBark屬性
        /// </summary>
        public IAnimalBark AnimalBark { get; set; }

        /// <summary>
        /// 放學
        /// </summary>
        public void LeaveSchool()
        {
            AnimalBark.Bark();
            Console.WriteLine("你家的熊孩子放學了⊙o⊙");
        }
    }
}

School

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using LinkTo.Test.Autofac.IService;

namespace LinkTo.Test.Autofac.Service
{
    /// <summary>
    /// 學生類
    /// </summary>
    public class Student : IStudent
    {
        /// <summary>
        /// 無參構造函數
        /// </summary>
        public Student()
        { }

        /// <summary>
        /// 有參構造函數
        /// </summary>
        /// <param name="studentID">學生ID</param>
        /// <param name="studentName">學生姓名</param>
        public Student(string studentID, string studentName)
        {
            Add(studentID, studentName);
        }

        /// <summary>
        /// 增加學生
        /// </summary>
        /// <param name="studentID">學生ID</param>
        /// <param name="studentName">學生姓名</param>
        public void Add(string studentID, string studentName)
        {
            Console.WriteLine($"新增的學生是：{studentName}");
        }
    }
}

Student

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using LinkTo.Test.Autofac.IService;

namespace LinkTo.Test.Autofac.Service
{
    /// <summary>
    /// 動物搖尾巴
    /// </summary>
    public class AnimalWagging
    {
        /// <summary>
        /// IAnimalBark屬性
        /// </summary>
        IAnimalBark animalBark;

        /// <summary>
        /// 有參構造函數
        /// </summary>
        /// <param name="bark">IAnimalBark變數</param>
        public AnimalWagging(IAnimalBark bark)
        {
            animalBark = bark;
        }

        /// <summary>
        /// 搖尾巴
        /// </summary>
        public virtual void Wagging()
        {
            animalBark.Bark();
            Console.WriteLine("搖尾巴");
        }

        /// <summary>
        /// 計數
        /// </summary>
        /// <returns></returns>
        public static int Count()
        {
            return 6;
        }

        /// <summary>
        /// 任務
        /// </summary>
        /// <param name="name">動物名稱</param>
        /// <returns></returns>
        public virtual async Task<string> WaggingAsync(string name)
        {
            var result = await Task.Run(() => Count());
            return $"{name}搖了{result}下尾巴";
        }
    }
}

AnimalWagging

2.2、Autofac安裝

Client項目右鍵->管理 NuGet 程式包->Autofac。

三、IoC-註冊

3.1、類型註冊

a）類型註冊：使用RegisterType進行註冊。

            //註冊Autofac組件
            ContainerBuilder builder = new ContainerBuilder();
            //註冊實現類Student，當我們請求IStudent介面的時候，返回的是類Student的對象。
            builder.RegisterType<Student>().As<IStudent>();
            //上面這句也可改成下麵這句，這樣請求Student實現了的任何介面的時候，都會返回Student對象。
            //builder.RegisterType<Student>().AsImplementedInterfaces();
            IContainer container = builder.Build();
            //請求IStudent介面
            IStudent student = container.Resolve<IStudent>();
            student.Add("1001", "Hello");

View Code

b）類型註冊(別名)：假如一個介面有多個實現類，可以在註冊時起別名。

            ContainerBuilder builder = new ContainerBuilder();
            builder.RegisterType<Dog>().Named<IAnimalSleep>("Dog");
            builder.RegisterType<Cat>().Named<IAnimalSleep>("Cat");
            IContainer container = builder.Build();

            var dog = container.ResolveNamed<IAnimalSleep>("Dog");
            dog.Sleep();
            var cat = container.ResolveNamed<IAnimalSleep>("Cat");
            cat.Sleep();

View Code

c）類型註冊(枚舉)：假如一個介面有多個實現類，也可以使用枚舉的方式註冊。

        public enum AnimalType
        {
            Dog,
            Cat
        }

View Code

            ContainerBuilder builder = new ContainerBuilder();
            builder.RegisterType<Dog>().Keyed<IAnimalSleep>(AnimalType.Dog);
            builder.RegisterType<Cat>().Keyed<IAnimalSleep>(AnimalType.Cat);
            IContainer container = builder.Build();

            var dog = container.ResolveKeyed<IAnimalSleep>(AnimalType.Dog);
            dog.Sleep();
            var cat = container.ResolveKeyed<IAnimalSleep>(AnimalType.Cat);
            cat.Sleep();

View Code

3.2、實例註冊

            ContainerBuilder builder = new ContainerBuilder();
            builder.RegisterInstance<IStudent>(new Student());
            IContainer container = builder.Build();

            IStudent student = container.Resolve<IStudent>();
            student.Add("1001", "Hello");

View Code

3.3、Lambda註冊

a）Lambda註冊

            ContainerBuilder builder = new ContainerBuilder();
            builder.Register(c => new Student()).As<IStudent>();
            IContainer container = builder.Build();

            IStudent student = container.Resolve<IStudent>();
            student.Add("1001", "Hello");

View Code

b）Lambda註冊(NamedParameter)

            ContainerBuilder builder = new ContainerBuilder();
            builder.Register<IAnimalSleep>((c, p) =>
                {
                    var type = p.Named<string>("type");
                    if (type == "Dog")
                    {
                        return new Dog();
                    }
                    else
                    {
                        return new Cat();
                    }
                }).As<IAnimalSleep>();
            IContainer container = builder.Build();

            var dog = container.Resolve<IAnimalSleep>(new NamedParameter("type", "Dog"));
            dog.Sleep();

View Code

3.4、程式集註冊

如果有很多介面及實現類，假如覺得這種一一註冊很麻煩的話，可以一次性全部註冊，當然也可以加篩選條件。

            ContainerBuilder builder = new ContainerBuilder();
            Assembly assembly = Assembly.Load("LinkTo.Test.Autofac.Service");   //實現類所在的程式集名稱
            builder.RegisterAssemblyTypes(assembly).AsImplementedInterfaces();  //常用
            //builder.RegisterAssemblyTypes(assembly).Where(t=>t.Name.StartsWith("S")).AsImplementedInterfaces();  //帶篩選
            //builder.RegisterAssemblyTypes(assembly).Except<School>().AsImplementedInterfaces();  //帶篩選
            IContainer container = builder.Build();

            //單實現類的用法
            IStudent student = container.Resolve<IStudent>();
            student.Add("1001", "Hello");

            //多實現類的用法
            IEnumerable<IAnimalSleep> animals = container.Resolve<IEnumerable<IAnimalSleep>>();
            foreach (var item in animals)
            {
                item.Sleep();
            }

View Code

3.5、泛型註冊

            ContainerBuilder builder = new ContainerBuilder();
            builder.RegisterGeneric(typeof(List<>)).As(typeof(IList<>));
            IContainer container = builder.Build();

            IList<string> list = container.Resolve<IList<string>>();

View Code

3.6、預設註冊

            ContainerBuilder builder = new ContainerBuilder();
            //對於同一個介面，後面註冊的實現會覆蓋之前的實現。
            //如果不想覆蓋的話，可以用PreserveExistingDefaults，這樣會保留原來註冊的實現。
            builder.RegisterType<Dog>().As<IAnimalSleep>();
            builder.RegisterType<Cat>().As<IAnimalSleep>().PreserveExistingDefaults();  //指定為非預設值
            IContainer container = builder.Build();

            var dog = container.Resolve<IAnimalSleep>();
            dog.Sleep();

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四、IoC-註入

4.1、構造函數註入

            ContainerBuilder builder = new ContainerBuilder();
            builder.RegisterType<AnimalWagging>();
            builder.RegisterType<Dog>().As<IAnimalBark>();
            IContainer container = builder.Build();

            AnimalWagging animal = container.Resolve<AnimalWagging>();
            animal.Wagging();

View Code

4.2、屬性註入

            ContainerBuilder builder = new ContainerBuilder();
            Assembly assembly = Assembly.Load("LinkTo.Test.Autofac.Service");                           //實現類所在的程式集名稱
            builder.RegisterAssemblyTypes(assembly).AsImplementedInterfaces().PropertiesAutowired();    //常用
            IContainer container = builder.Build();

            ISchool school = container.Resolve<ISchool>();
            school.LeaveSchool();

View Code

五、IoC-事件

Autofac在組件生命周期的不同階段，共對應了5個事件，執行順序如下所示：

1.OnRegistered->2.OnPreparing->3.OnActivating->4.OnActivated->5.OnRelease

            ContainerBuilder builder = new ContainerBuilder();
            builder.RegisterType<Student>().As<IStudent>()
                .OnRegistered(e => Console.WriteLine("OnRegistered：在註冊的時候調用"))
                .OnPreparing(e => Console.WriteLine("OnPreparing：在準備創建的時候調用"))
                .OnActivating(e => Console.WriteLine("OnActivating：在創建之前調用"))
                //.OnActivating(e => e.ReplaceInstance(new Student("1000", "Test")))
                .OnActivated(e => Console.WriteLine("OnActivated：在創建之後調用"))
                .OnRelease(e => Console.WriteLine("OnRelease：在釋放占用的資源之前調用"));
            using (IContainer container = builder.Build())
            {
                IStudent student = container.Resolve<IStudent>();
                student.Add("1001", "Hello");
            }

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六、IoC-生命周期

6.1、Per Dependency

Per Dependency：為預設的生命周期，也被稱為"transient"或"factory"，其實就是每次請求都創建一個新的對象。

            ContainerBuilder builder = new ContainerBuilder();
            Assembly assembly = Assembly.Load("LinkTo.Test.Autofac.Service");                                                   //實現類所在的程式集名稱
            builder.RegisterAssemblyTypes(assembly).AsImplementedInterfaces().PropertiesAutowired().InstancePerDependency();    //常用
            IContainer container = builder.Build();

            ISchool school1 = container.Resolve<ISchool>();
            ISchool school2 = container.Resolve<ISchool>();
            Console.WriteLine(school1.Equals(school2));

View Code

6.2、Single Instance

Single Instance：就是每次都用同一個對象。

            ContainerBuilder builder = new ContainerBuilder();
            Assembly assembly = Assembly.Load("LinkTo.Test.Autofac.Service");                                           //實現類所在的程式集名稱
            builder.RegisterAssemblyTypes(assembly).AsImplementedInterfaces().PropertiesAutowired().SingleInstance();   //常用
            IContainer container = builder.Build();

            ISchool school1 = container.Resolve<ISchool>();
            ISchool school2 = container.Resolve<ISchool>();
            Console.WriteLine(ReferenceEquals(school1, school2));

View Code

6.3、Per Lifetime Scope

Per Lifetime Scope：同一個Lifetime生成的對象是同一個實例。

            ContainerBuilder builder = new ContainerBuilder();
            builder.RegisterType<School>().As<ISchool>().InstancePerLifetimeScope();
            IContainer container = builder.Build();
            ISchool school1 = container.Resolve<ISchool>();
            ISchool school2 = container.Resolve<ISchool>();
            Console.WriteLine(school1.Equals(school2));
            using (ILifetimeScope lifetime = container.BeginLifetimeScope())
            {
                ISchool school3 = lifetime.Resolve<ISchool>();
                ISchool school4 = lifetime.Resolve<ISchool>();
                Console.WriteLine(school3.Equals(school4));
                Console.WriteLine(school2.Equals(school3));
            }

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七、IoC-通過配置文件使用Autofac

7.1、組件安裝

Client項目右鍵->管理 NuGet 程式包->Autofac.Configuration及Microsoft.Extensions.Configuration.Xml。

7.2、配置文件

新建一個AutofacConfigIoC.xml文件，在其屬性的複製到輸出目錄項下選擇始終複製。

<?xml version="1.0" encoding="utf-8" ?>
<autofac defaultAssembly="LinkTo.Test.Autofac.IService">
  <!--無註入-->
  <components name="1001">
    <type>LinkTo.Test.Autofac.Service.Student, LinkTo.Test.Autofac.Service</type>
    <services name="0" type="LinkTo.Test.Autofac.IService.IStudent" />
    <injectProperties>true</injectProperties>
  </components>
  <components name="1002">
    <type>LinkTo.Test.Autofac.Service.Dog, LinkTo.Test.Autofac.Service</type>
    <services name="0" type="LinkTo.Test.Autofac.IService.IAnimalBark" />
    <injectProperties>true</injectProperties>
  </components>
  <!--構造函數註入-->
  <components name="2001">
    <type>LinkTo.Test.Autofac.Service.AnimalWagging, LinkTo.Test.Autofac.Service</type>
    <services name="0" type="LinkTo.Test.Autofac.Service.AnimalWagging, LinkTo.Test.Autofac.Service" />
    <injectProperties>true</injectProperties>
  </components>
  <!--屬性註入-->
  <components name="3001">