在ASP.NET Core中，是否可以通过Program.cs设置中间件? [英] in ASP.NET Core, is there any way to set up middleware from Program.cs?

问题描述

我正在为ASP.NET Core网站构建一个支持库.我有一些中间件需要启用，并且由于其作用，需要在任何其他中间件之前添加它们.

I am building a support library for ASP.NET Core websites. I have a few pieces of middleware that need to be enabled, and they need to be added before any other middleware due what they do.

我可以在IWebHostBuilder上创建扩展方法来添加服务，同样用于配置日志记录，但是我看不到以编程方式添加中间件的任何方法.有什么办法吗?在查看WebHost/WebHostBuilder的源代码时，没有发现任何问题.

I can create an extension method on IWebHostBuilder to add services, likewise for configuring logging, but I don't see any way to add middleware in a programmatic way. Is there any way to do this? Looking at the source for WebHost/WebHostBuilder nothing jumped out.

鉴于第一个评论，我可能还不够清楚.我知道如何创建和使用中间件.我正在尝试做的是确保当框架在启动时调用Configure(IApplicationBuilder app)方法时，我的中间件已经到位.以类似于甚至可以在启动之前执行ServiceConfiguration的方式.像这样的扩展方法

Given the first comment, I may not have been clear enough. I know how to create middleware and use it. What I am trying to do is ensure that when the Configure(IApplicationBuilder app) method is called on Startup by the framework, my middleware is already in place. In a similar manner to being able to do ServiceConfiguration prior to Startup even being created. So an extension method like

public static IWebHostBuilder AddPayscaleHostingServices(this IWebHostBuilder webHostBuilder, string serviceName)
{
    return webHostBuilder.ConfigureServices(collection =>
    {
        collection.RegisterPayscaleHostingServices();
    }).ConfigureLogging(factory =>
    {

    });
}

使我能够在webHostBuilder.Build方法之前进行一些设置，但对于IApplicationBuilder上的中间件/任何东西，我看不到任何类似的东西.

gives me the ability to do some setup prior to the webHostBuilder.Build method, but I don't see anything similar for middleware/anything on IApplicationBuilder.

谢谢，埃里克

推荐答案

您可以使用启动过滤器来实现此目的.启动过滤器使您可以从DI容器解析的服务中配置中间件.

You could use a startup filter to achieve this. Startup filters allow you to configure middleware from a service resolved from the DI container.

定义启动过滤器很容易:

Defining a startup filter is easy:

public class MyStartupFilter : IStartupFilter
{
    public Action<IApplicationBuilder> Configure(Action<IApplicationBuilder> next)
    {
        return app =>
        {
            // Configure middleware
            // ...

            // Call the next configure method
            next(app);
        };
    }
}

始终确保调用 next(app)或不会配置任何其他中间件.

Always make sure to call next(app) or any other middleware won't be configured.

现在在 ConfigureServices 方法中将启动过滤器注册为 IStartupFilter 的单例实现:

Now register the startup filter as a singleton implementation of IStartupFilter in your ConfigureServices method:

services.AddSingleton<IStartupFilter, MyStartupFilter>();

这篇关于在ASP.NET Core中，是否可以通过Program.cs设置中间件?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！