Use Middleware in ASP.NET Core MVC 5

Create ASP.NET Core MVC 5 Project

On the Visual Studio, select Create a new project from Get Started

Select ASP.NET Core Web Application

Input Project Name and select Location for new project

Select ASP.NET Core 5.0 Version and select ASP.NET Core Empty Template. Click Create button to finish

Add Middleware

Create new folder named Middlewares. In this folder, create new middlewares as below:

DateLog Middleware

In Middlewares folder, create new class named DateLogMiddleware.cs as below:

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using System;
using System.Diagnostics;
using System.Threading.Tasks;

namespace LearnASPNETCoreMVC5.Middlewares
{
    // You may need to install the Microsoft.AspNetCore.Http.Abstractions package into your project
    public class DateLogMiddleware
    {
        private readonly RequestDelegate _next;

        public DateLogMiddleware(RequestDelegate next)
        {
            _next = next;
        }

        public Task Invoke(HttpContext httpContext)
        {
            Debug.WriteLine("Date: " + DateTime.Now.ToLongDateString());
            return _next(httpContext);
        }
    }

    // Extension method used to add the middleware to the HTTP request pipeline.
    public static class DateLogMiddlewareExtensions
    {
        public static IApplicationBuilder UseDateLogMiddleware(this IApplicationBuilder builder)
        {
            return builder.UseMiddleware<DateLogMiddleware>();
        }
    }
}

Browser Middleware

In Middlewares folder, create new class named BrowserMiddleware.cs as below:

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using System.Diagnostics;
using System.Threading.Tasks;

namespace LearnASPNETCoreMVC5.Middlewares
{
    // You may need to install the Microsoft.AspNetCore.Http.Abstractions package into your project
    public class BrowserMiddleware
    {
        private readonly RequestDelegate _next;

        public BrowserMiddleware(RequestDelegate next)
        {
            _next = next;
        }

        public Task Invoke(HttpContext httpContext)
        {
            var userAgent = httpContext.Request.Headers["User-Agent"].ToString();
            var ipAddress = httpContext.Connection.RemoteIpAddress.ToString();
            var url = httpContext.Request.Path;
            Debug.WriteLine("User Agent: " + userAgent);
            Debug.WriteLine("IP: " + ipAddress);
            Debug.WriteLine("Url: " + url);
            return _next(httpContext);
        }
    }

    // Extension method used to add the middleware to the HTTP request pipeline.
    public static class BrowserMiddlewareExtensions
    {
        public static IApplicationBuilder UseBrowserMiddleware(this IApplicationBuilder builder)
        {
            return builder.UseMiddleware<BrowserMiddleware>();
        }
    }
}

Add Configurations

Open Startup.cs file and add new configurations as below:

using LearnASPNETCoreMVC5.Middlewares;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;

namespace LearnASPNETCoreMVC5
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddControllersWithViews();
        }

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            // Add Middlewares
            app.UseMiddleware<DateLogMiddleware>();
            app.UseMiddleware<BrowserMiddleware>();

            app.UseRouting();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllerRoute(
                    name: "default",
                    pattern: "{controller=Demo}/{action=Index}/{id?}");
            });
        }
    }
}

Create Controller

Create new folder named Controllers. In Controllers folder, create new controller as below:

Home Controller

Create new controller named HomeController.cs as below:

using Microsoft.AspNetCore.Mvc;

namespace LearnASPNETCoreMVC5.Controllers
{
    [Route("home")]
    public class HomeController : Controller
    {
        [Route("")]
        [Route("index")]
        [Route("~/")]
        public IActionResult Index()
        {
            return View();
        }
    }
}

Create View

In Views folder, create new views as below:

Home Views

In Views/Home folder, create new view named Index.cshtml as below:

<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Index</title>
</head>
<body>

    <h3>Home Page</h3>

</body>
</html>

Structure of ASP.NET Core MVC 5 Project

Run Application

Access Index action in Home controller with following url: http://localhost:48982/home/index

Output

Date: Saturday, May 5, 2018
User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0
IP: ::1
Url: /home/index