ASP.NET Core Hello Word with SampleMiddleware

Program.cs

using System;
using System.Threading.Tasks;
using Microsoft.AspNetCore;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;

namespace WebApplication1
{
    public class Program
    {
        public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .UseStartup<Startup>();

        public static void Main(string[] args)
        {
            CreateWebHostBuilder(args).Build().Run();
        }
    }

    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            app.UseMiddleware<SampleMiddleware>();
            app.Run(async (context) => { await context.Response.WriteAsync("Hello World!"); });
        }
    }

    public class SampleMiddleware
    {
        private readonly RequestDelegate _next;

        public SampleMiddleware(RequestDelegate next)
        {
            this._next = next;
        }

        public async Task Invoke(HttpContext context)
        {
            Console.WriteLine($"{context.Request.Path}{context.Request.QueryString}");
            await this._next(context);
        }
    }
}