startup

startup.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;

namespace Custom_Midlleware
{
    public class Startup
    {
        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole();

            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.Use(async (context, next) =>
            {
                await context.Response.WriteAsync("First Middleware! <br/>");
                await next.Invoke();
                await context.Response.WriteAsync("While returning from Run!! <br/>");
            });

            app.Map("/myview", (builder) =>
            {
                builder.Run(async (context) =>
                {
                    await context.Response.WriteAsync("Hello From Map Component!<br/>");
                });
            });

            app.MapWhen(context => context.Request.Query.ContainsKey("something"), (builder) =>
            {
                builder.Use(async (context, next) =>
                {
                    await context.Response.WriteAsync("Using Use Extension from MapWhen extension!!<br/>");
                    await next.Invoke();
                });
                
                builder.Run(async (context) =>
                {
                    await context.Response.WriteAsync("Hi, From MapWhen Extension!<br/>");
                });
            });
            app.Run(async (context) =>
            {
                await context.Response.WriteAsync("Hello World!<br/>");
            });

           
        }
    }
}