c# - 获取 Controller 中的当前 IServiceScope

Question

如何获得当前(按请求)IServiceScope 的实例在 Controller 中？在服务中？

计划是使用它来解析属于同一范围的服务。

Answer 1

get an instance ... in a controller:

无需使用IHttpContextAccessor在 内 Controller .已经有 HttpContext property 为你。如果您想访问HttpContext ， 只是

// no need to use IHttpContextAccessor.HttpContext
var svc = HttpContext.RequestServices.GetService<MyService>();

或者作为替代方案，注入(inject) IServiceProvider直接地:

public class MyController : Controller
{
    private IServiceProvider _sp;
    public MyController(IServiceProvider sp)
    {
        this._sp = sp;
    }
}

当你想要一个小范围时，你可以如下创建它:

public IActionResult MyActoin()
{
    // create a more small scope
    using (var scope = this._sp.CreateScope())
    {
        var sp = scope.ServiceProvider;
        // now you get the services from this small scope
        var svc1 = sp.GetRequiredService<MyService1>();
        var svc2 = sp.GetRequiredService<MyService2>();
        //...
    }
    return new JsonResult("it works");
}

特别是，如果所需服务的范围恰好是请求范围，只需将它们全部注入(inject):

public class MyController : Controller
{
    private IServiceProvider _sp;
    private readonly MyService1 _service1;
    private readonly MyService2 _service2;

    public MyController(IServiceProvider sp, MyService1 service1, MyService2 service2,...)
    {
        this._sp = sp;
        this._service1 = service1;
        this._service2 = service2;
    }