构建RequestDelegate管道

1. 创建 Context.cs

using System;
using System.Threading.Tasks;

namespace MyPipeline
{
   public class Context{

   }
}

2. 创建 RequestDelegate.cs

using System;
using System.Threading.Tasks;

namespace MyPipeline
{
   public delegate Task RequestDelegate(Context context);
}

3. 具体实现

using System;
using System.Collections.Generic;
using System.Threading.Tasks; 

namespace MyPipeline {
    class Program {

        public static List < Func < RequestDelegate, RequestDelegate >> _list = new List < Func < RequestDelegate, RequestDelegate >> ();
        static void Main(string[] args) {

           Use(next =>  {
                return context =>  {
                    System.Console.WriteLine("");
                return  next.Invoke(context);
                };
            }); 

            Use(next =>  {
                return context =>  {
                    System.Console.WriteLine("");
                return  next.Invoke(context);
                };
            }); 

            RequestDelegate end = (context) =>  {
                        System.Console.WriteLine("end ... ");
                            return Task.CompletedTask; 

            }; 

            _list.Reverse();
            foreach (var middleware in _list) {
                end = middleware.Invoke(end); 

            }

            end.Invoke(new Context()); 

            Console.ReadLine(); 

        }

        public static void Use(Func < RequestDelegate, RequestDelegate > middleware) {
            _list.Add(middleware);
        }
    }
}

4. 运行结果

end ...