ASP.NET Core 作用域与对象释放行为 （基础）[学习笔记]

• ASP.NET Core 作用域与对象释放行为 （基础）[学习笔记]
  • 知识大纲
  • 代码准备
    • 项目结构
    • 项目中相关代码
  • Transient
  • Singleton
  • Scoped
  • 项目地址

知识大纲

作用域

• IServiceScope

实现IDisposable接口类型的释放

• DI只负责释放由其创建的对象实例
• DI在容器或子容器释放时，释放由其创建的对象实例

代码准备

项目结构

项目中相关代码

OrderService.cs

public interface IOrderService
{
}
public class DisposableOrderService : IOrderService, IDisposable
{
    public void Dispose()
    {
        Console.WriteLine($"DisposableOrderService Disposed:{this.GetHashCode()}");
    }
}

WeatherForecastController.cs

[HttpGet]
public int Get(
    [FromServices]IOrderService orderService,
    [FromServices]IOrderService orderService2,
    [FromServices]IHostApplicationLifetime hostApplicationLifetime,
  [FromQuery]bool stop = false
)
{
    #region 
    Console.WriteLine("=======1=========="+ " orderService :"+ orderService.GetHashCode());
    using (IServiceScope scope = HttpContext.RequestServices.CreateScope())
    {
        var service = scope.ServiceProvider.GetService<IOrderService>();
        var service2 = scope.ServiceProvider.GetService<IOrderService>();
        Console.WriteLine("=======2==========" + " service :" + service.GetHashCode());
        Console.WriteLine("=======2==========" + " service2 :" + service2.GetHashCode());
    }
    Console.WriteLine("=======3==========" + " orderService2 :" + orderService2.GetHashCode());
    #endregion
    #region
    if (stop)
    {
        hostApplicationLifetime.StopApplication();
    }
    #endregion
    Console.WriteLine("接口请求处理结束");
    return 1;
}

Startup.cs

public void ConfigureServices(IServiceCollection services)
{
    services.AddTransient<IOrderService, DisposableOrderService>();
    //services.AddSingleton<IOrderService>(p=>new DisposableOrderService());
    //services.AddScoped<IOrderService, DisposableOrderService>();
    services.AddControllers();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env, IHostApplicationLifetime hostApplicationLifetime)
{
    //var s = app.ApplicationServices.GetService<IOrderService>();
    //var s2 = app.ApplicationServices.GetService<IOrderService>();
    if (env.IsDevelopment())
    {
        app.UseDeveloperExceptionPage();
    }
    app.UseRouting();
    app.UseAuthorization();
    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });
}

Transient

services.AddTransient<IOrderService, DisposableOrderService>();

Singleton

services.AddSingleton<IOrderService>(p=>new DisposableOrderService());

Scoped

services.AddScoped<IOrderService, DisposableOrderService>();

从上述来看可以清晰的看到对象的释放情况，这里我们可以通过stop为true时再次去观察情况

项目地址

GitHub: https://github.com/AiDaShi/GeekTimeLearning