Autofac 依赖注入教程

Myth丶恋晨 2022-02-01 05:04 213阅读 0赞

1.  安装 Autofac: Install-Package Autofac -Version 4.8.1
2.  创建两个类库项目，IService (用于编写接口)，ServiceImpl（用于创建实现类）

IService 下  
public interface IAnimalBark  
\{  
void Bark();  
\}

public interface IAnimalSleep  
\{  
void Sleep();  
\}

public interface IUser  
\{  
void AddNew(string name, string pwd);  
\}

public interface ISchool  
\{  
void AfterSchool();  
\}

ServiceImpl下  
public class Dog : IAnimalBark,IAnimalSleep  
\{  
public void Bark()  
\{  
Console.WriteLine(“汪汪汪汪汪”);  
\}

public void Sleep()  
\{  
Console.WriteLine(“zZ,睡着了”);  
\}  
\}

public class Cat : IAnimalBark  
\{  
public void Bark()  
\{  
Console.WriteLine(“喵喵喵”);  
\}  
\}

public class User : IUser  
\{  
public void AddNew(string name, string pwd)  
\{  
Console.WriteLine(“添加新的用户:” + name);  
\}  
\}

public class School : ISchool  
\{  
public IAnimalBark dog \{ get; set; \}  
public void AfterSchool()  
\{  
dog.Bark();  
Console.WriteLine(“放学了”);  
\}  
\}

1.  原理性使用方法，如果再有一个接口和一个实现类，那就再注册一次

ContainerBuilder builder = new ContainerBuilder();  
//注册实现类Dog,当我们 请求IAnimalBark接口 的时候返回的是类Dog的对象,原理性的代码  
builder.RegisterType().As();  
//上面一句也可改成下面一句，这样 请求Dog实现的任何接口 的时候都会返回Dog对象,原理性的代码  
//builder.RegisterType().AsImplementedInterfaces();  
IContainer container = builder.Build();  
//请求IAnimalBark接口  
IAnimalBark dog = container.Resolve();  
dog.Bark();  
Console.ReadKey();

1.  如果有很多接口，很多实现类，每次都要注册一次会很麻烦，可以如下进行一次注册

ContainerBuilder builder = new ContainerBuilder();  
Assembly asm = Assembly.Load(“Service”);//实现类所在的程序集名称  
builder.RegisterAssemblyTypes(asm).AsImplementedInterfaces();//常用  
IContainer container = builder.Build();  
IAnimalBark dog = container.Resolve();  
IUser user = container.Resolve();  
dog.Bark();  
user.AddNew(“baidu”,“123”);  
Console.ReadKey();

1.  如果有多个实现类，container.Resolve();只会返回其中一个对象，如果想返回多个类的对象，应改成container.Resolve<IEnumerable>();

ContainerBuilder builder = new ContainerBuilder();  
Assembly asm = Assembly.Load(“Service”);//实现类所在的程序集名称  
builder.RegisterAssemblyTypes(asm).AsImplementedInterfaces();//常用  
IContainer container = builder.Build();  
IEnumerable animals = container.Resolve<IEnumerable>();  
foreach(var animal in animals)  
\{  
animal.Bark();  
\}  
Console.ReadKey();

1.  如果一个实现类中定义了其他类型的属性（接口类型的属性），在注册时又加上builder.RegisterAssemblyTypes(asm).AsImplementedInterfaces().PropertiesAutowired();这样会给属性进行“注入”

ContainerBuilder builder = new ContainerBuilder();  
Assembly asm = Assembly.Load(“Service”);//实现类所在的程序集名称  
builder.RegisterAssemblyTypes(asm).AsImplementedInterfaces().PropertiesAutowired();//常用  
IContainer container = builder.Build();  
ISchool school = container.Resolve();  
school.AfterSchool();  
Console.ReadKey();

1.  可以通过在builder.RegisterAssemblyTypes(asm)后面以 Instance\*\*\*()配置来实现Auto对象的生命周期

InstancePerDependency()每次Resolve都返回新的对象  
ContainerBuilder builder = new ContainerBuilder();  
Assembly asm = Assembly.Load(“Service”);//实现类所在的程序集名称  
builder.RegisterAssemblyTypes(asm).AsImplementedInterfaces().PropertiesAutowired().InstancePerDependency();//常用  
IContainer container = builder.Build();  
ISchool school = container.Resolve();  
ISchool school2 = container.Resolve();  
Console.WriteLine(school.Equals(school2));  
Console.ReadKey();

SingleInstance()每次Resolve都返回同一个对象，推荐  
ContainerBuilder builder = new ContainerBuilder();  
Assembly asm = Assembly.Load(“Service”);//实现类所在的程序集名称  
builder.RegisterAssemblyTypes(asm).AsImplementedInterfaces().PropertiesAutowired().SingleInstance();//常用  
IContainer container = builder.Build();  
ISchool school = container.Resolve();  
ISchool school2 = container.Resolve();  
Console.WriteLine(object.ReferenceEquals(school,school2));  
Console.ReadKey();