.Net6 web API (IOC容器内置)

前沿

内置I0C容器使用

1.分层架构，上层调用下层1
2.具备抽象【接口和抽象类】和实现【普通类】
3.注册抽象和具体之间的关系
4.通过构造函数注入【内置容器仅支持构造函数注入】

IOC容器的主要作用是管理应用程序中的各种服务、组件和依赖关系，并在需要时将它们注入到其他组件中。通过IOC容器，我们可以实现解耦、灵活配置和可替换性等优势。

注册服务：在应用程序启动时，通过IOC容器的API将服务注册到容器中，告诉容器如何创建和管理这些服务。通常在Program.cs文件中进行注册。

解析依赖：在需要使用服务的地方，通过IOC容器获取服务的实例，而不是直接创建实例。容器会自动解析服务的依赖关系，并创建正确的实例。

使用服务：使用从IOC容器中获取的服务实例来完成相应的业务逻辑。

新建项目

 interfaces: ITestServiceA

namespace yanfanNet6Interfaces;

public interface ITestServiceA
{
    public string ShowA();
}

TestServiceA

using yanfanNet6Interfaces;

namespace yanfanNet6Services;
public class TestServiceA : ITestServiceA
{
    public TestServiceA()
    {
        Console.WriteLine($"{GetType().Name} 被供找");
        }

    public string ShowA()
    {
        return $"this is from {GetType().FullName} ShowA";
        }

}

TestServiceB

using yanfanNet6Interfaces;

namespace yanfanNet6Services;
public class TestServiceB : ITestServiceB
{
    public ITestServiceA _TestServiceA;
    public TestServiceB(ITestServiceA testServiceA)
    {
        _TestServiceA = testServiceA;
        Console.WriteLine($"{GetType().Name} 被构招");
    }

    /// <summary>
    /// 
    /// </summary>
    /// <returns></returns>
    public string ShowB()
    {
        return $"this is from {GetType().FullName} ShowB 调用{_TestServiceA.ShowA()}" ;
    }

}

　　TestServiceB 则是 依赖了 TestService A

然后在新建控制器

using System;
using Microsoft.AspNetCore.Mvc;
using yanfanNet6Interfaces;
using yanfanNet6Services;

using yanfanNet6WebApi.Utility.Swagger;

namespace yanfanNet6WebApi.Controllers;

/// <summary>
/// 文件资源
/// </summary>
[ApiController]
[Route("[controller]")]
[ApiVersion("2.0")]
public class IocContainerController : ControllerBase
{

    private readonly ILogger<IocContainerController> _logger;

    private readonly ITestServiceA _ITestServiceA;
    private readonly ITestServiceB _ITestServiceB;
    private readonly IServiceProvider _IServiceProvider;

    public IocContainerController(ILogger<IocContainerController> logger,
        ITestServiceA iTestServiceA, ITestServiceB iTestServiceB, IServiceProvider iServiceProvider)
    {
        _logger = logger;
        _ITestServiceA = iTestServiceA;
        _ITestServiceB = iTestServiceB;
        _IServiceProvider = iServiceProvider;
    }

    /// <summary>
    /// 
    /// </summary>
    /// <param name="iTestServiceBNew"></param>
    /// <param name="iServiceProvider"></param>
    /// <returns></returns>
    [HttpGet()]
    public string ShowA([FromServices] ITestServiceB iTestServiceBNew, [FromServices]
    IServiceProvider iServiceProvider)
    {
        //TestServiceA testServiceA = new TestServiceA();

        ITestServiceB testServiceB1 = _IServiceProvider.GetService<ITestServiceB>();
        ITestServiceB testServiceB2 = iServiceProvider.GetService<ITestServiceB>();
        return _ITestServiceA.ShowA();
    }

    [HttpPost()]
    public string ShowB()
    {
        return _ITestServiceB.ShowB();
    }
}

然后把2个依赖注入进来

 看这段代码

    [HttpGet()]
    public string ShowA([FromServices] ITestServiceB iTestServiceBNew, [FromServices]
    IServiceProvider iServiceProvider)
    {
        //TestServiceA testServiceA = new TestServiceA();

        ITestServiceB testServiceB1 = _IServiceProvider.GetService<ITestServiceB>();
        ITestServiceB testServiceB2 = iServiceProvider.GetService<ITestServiceB>();
        return _ITestServiceA.ShowA();
    }

/TestServiceA testServiceA = new TestServiceA(); 需要在你的方法里面 这里是直接创建了实例

如果使用这个

在program.cs 文件下 写这个

        #region 注册抽象和具体之间的关系
        builder.Services.AddTransient<ITestServiceA, TestServiceA>();
        builder.Services.AddTransient<ITestServiceB, TestServiceB>();
        #endregion

需要使用服务的地方，通过IOC容器获取服务的实例，而不是直接创建实例

然后再运行就OK了