static void Main(string[] args) { var app = new ApplicationBuilder(); var http = new HttpContext(); app.Use(next => { return(new RequestDelegate((d) => { Console.WriteLine("我是item01方法"); return next(http); })); }); app.Use(next => { return(new RequestDelegate((d) => { Console.WriteLine("我是item02方法"); return next(http); })); }); app.Use(next => { return(new RequestDelegate((d) => { Console.WriteLine("我是item03方法"); return next(http); })); }); app.UserItem04(http); app.Build().Invoke(http); }