如何在ASP.NET Core中使用IApplicationBuilder中间件重载

本文介绍了如何在ASP.NET Core中使用IApplicationBuilder中间件重载的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

ASP.NET Core为app.Use()方法提供了两个重载.通常我们只使用一个重载

ASP.NET Core provides two overloads for app.Use() method. Usually we use only one overload that is

app.Use(Func<HttpContext,Func<Task>, Task> middleware)

用作

app.Use(async (context, next) => { await context.Response.WriteAsync("1st middleware <br/>"); await next.Invoke(); });

我要使用的另一个重载是

The other overload that i want to use is

app.Use(Func<RequestDelegate,RequestDelegate> middleware)

我找不到如何使用此重载的示例.任何想法都会很棒.

I couldn't find an example of how we can use this overload. Any ideas will be great.

推荐答案

Func<RequestDelegate, RequestDelegate>是一个委托，它接受一个委托并返回一个委托.您可以将其与以下lambda表达式一起使用:

Func<RequestDelegate, RequestDelegate> is a delegate, which accepts a delegate and returns a delegate. You can use it with this lambda expression:

app.Use(next => async context => { await context.Response.WriteAsync("Hello, World!"); await next(context); }