.NETCore 服务的三种生命周期

一、接口定义

  public interface ITestSerivceSingleton
  {
      public string GetServiceNameBase() {
          return "ITestSerivceSingleton";
      }

      public string GetServiceName();
  }

    public interface ITestSerivceScoped
    {
        public string GetServiceNameBase()
        {
            return "ITestSerivceScoped";
        }

        public string GetServiceName();

    }

  public interface ITestSerivceTransient
  {
      public string GetServiceNameBase() {
          return "ITestSerivceTransient";
      }

      public string GetServiceName();
  }

二、实现接口

    public class TestSerivceScoped : ITestSerivceScoped
    {
        public string Name { get; set; }

        public TestSerivceScoped()
        {
            Name = Guid.NewGuid().ToString();
        }
        public string GetServiceName()
        {
            return "TestSerivceScoped" + Name;
        }
    }

  public class TestSerivceSingleton : ITestSerivceSingleton
  {
      public string Name { get; set; }

      public TestSerivceSingleton()
      {
          Name = Guid.NewGuid().ToString();
      }
      public string GetServiceName()
      {
          return "TestSerivceSingleton" +Name;
      }
  }

 public class TestSerivceTransient : ITestSerivceTransient
 {
     public string Name { get; set; }

     public TestSerivceTransient()
     {
         Name = Guid.NewGuid().ToString();
     }
     public string GetServiceName()
     {
         return "TestSerivceTransient" + Name;
     }
 }

三、服务注册（.NetCore自带IOC容器）

builder.Services.AddTransient<ITestSerivceTransient,TestSerivceTransient>();
builder.Services.AddScoped<ITestSerivceScoped, TestSerivceScoped>();
builder.Services.AddSingleton<ITestSerivceSingleton, TestSerivceSingleton>();

四、测试作用域

 [Route("api/[controller]")]
 [ApiController]
 public class HomeController : ControllerBase
 {
     private readonly ITestSerivceSingleton testSerivceSingleton;
     private readonly ITestSerivceScoped testSerivceScoped;
     private readonly ITestSerivceTransient testSerivceTransient;
     private readonly ITestSerivceSingleton testSerivceSingleton1;
     private readonly ITestSerivceScoped testSerivceScoped1;
     private readonly ITestSerivceTransient testSerivceTransient1;
     public HomeController(ITestSerivceSingleton testSerivceSingleton,ITestSerivceScoped testSerivceScoped,ITestSerivceTransient testSerivceTransient,
         ITestSerivceSingleton testSerivceSingleton1, ITestSerivceScoped testSerivceScoped1, ITestSerivceTransient testSerivceTransient1) {
         this.testSerivceSingleton = testSerivceSingleton;
         this.testSerivceScoped = testSerivceScoped;
         this.testSerivceTransient = testSerivceTransient;
         this.testSerivceSingleton1 = testSerivceSingleton1;
         this.testSerivceScoped1 = testSerivceScoped1;
         this.testSerivceTransient1 = testSerivceTransient1;
     }

     [HttpGet("Index")]
     public IActionResult Index()
     {
        StringBuilder stringBuilder = new StringBuilder();
         stringBuilder.AppendLine(testSerivceSingleton.GetServiceNameBase());
         stringBuilder.AppendLine(testSerivceSingleton.GetServiceName());
         stringBuilder.AppendLine(testSerivceSingleton1.GetServiceName());
         stringBuilder.AppendLine(testSerivceScoped.GetServiceNameBase());
         stringBuilder.AppendLine(testSerivceScoped.GetServiceName());
         stringBuilder.AppendLine(testSerivceScoped1.GetServiceName());
         stringBuilder.AppendLine(testSerivceTransient.GetServiceNameBase());
         stringBuilder.AppendLine(testSerivceTransient.GetServiceName());
         stringBuilder.AppendLine(testSerivceTransient1.GetServiceName());

         return Content(stringBuilder.ToString());
     }
 }

五、测试结果

六、验证结论

Singleton（单例服务）：每次请求都是同一个服务实例

Scoped（作用域服务）：同一次请求时同一个服务实例，不同请求服务实例不同

Transient（瞬时服务）：同一次或不同请求中每次使用的服务实例都是新的实例

当Singleton中包含Scoped、Transient成员，Scoped、Transient成员生命周期会改变

Scoped、Transient中包含Singleton，Singleton成员生命周期不变

单例对象会改变成员的生命周期

单例对象生命周期无法改变