Introduction
In this article, I will explain how to install .NET Core tools preview for Visual Studio and how to print “Hello World” in the latest ASP.NET Core 1.0.
Step 1
First download Visual Studio 2015 with Update 3 through the link click here.
Step 2
Go to Install .NET Core tools preview for Visual Studio. This .NET Core tools adds support for .NET Core projects in Visual Studio 2015.

Install DotNet Core
Step 3
This is really interesting. Open Visual Studio 2015 and create new Project.

Open Templates – > Visual C# -> Click .NET Core Category and you can see “ASP.NET Core Web Application” template.

DotnetCore Template in VS 2015

Step 4
Select Empty Templates ( based on your requirement ) in ASP.NET Core Templates Category if you are going to host the app in Microsoft Azure Service and check in the “Host in the cloud option”.

DotNet Core Empty Page

Step 5
Open “Startup.cs” class in “HelloWorldDotnetCore” project folder.



Step 6
We are creating mini middle ware Application, using lambda expression in “app.Run”. This piece of code is creating “Hello World”.
C# Code
  1. using System;
  2. using System.Collections.Generic;
  3. using System.Linq;
  4. using System.Threading.Tasks;
  5. using Microsoft.AspNetCore.Builder;
  6. using Microsoft.AspNetCore.Hosting;
  7. using Microsoft.AspNetCore.Http;
  8. using Microsoft.Extensions.DependencyInjection;
  9. using Microsoft.Extensions.Logging;
  11. namespace HelloWorldDotnetCore
  12. {
  13. public class Startup
  14. {
  15. // This method gets called by the runtime. Use this method to add services to the container.
  16. // For more information on how to configure your application, visit http://go.microsoft.com/fwlink/?LinkID=398940
  17. public void ConfigureServices(IServiceCollection services)
  18. {
  19. }
  21. // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
  22. public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
  23. {
  24. loggerFactory.AddConsole();
  26. if (env.IsDevelopment())
  27. {
  28. app.UseDeveloperExceptionPage();
  29. }
  30. app.Run(async (context) =>
  31. {
  32. await context.Response.WriteAsync(" Hello World! ");
  33. });
  35. }
  36. }
  37. }
Output 1
Step 7
“app.run” doesn’t work in .NET Core followed by using “app.Use”. It will pass two parameters and add the next middleware content In .NET Core.
C# Code
  1. using System;
  2. using System.Collections.Generic;
  3. using System.Linq;
  4. using System.Threading.Tasks;
  5. using Microsoft.AspNetCore.Builder;
  6. using Microsoft.AspNetCore.Hosting;
  7. using Microsoft.AspNetCore.Http;
  8. using Microsoft.Extensions.DependencyInjection;
  9. using Microsoft.Extensions.Logging;
  11. namespace HelloWorldDotnetCore
  12. {
  13. public class Startup
  14. {
  15. // This method gets called by the runtime. Use this method to add services to the container.
  16. // For more information on how to configure your application, visit http://go.microsoft.com/fwlink/?LinkID=398940
  17. public void ConfigureServices(IServiceCollection services)
  18. {
  19. }
  21. // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
  22. public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
  23. {
  24. loggerFactory.AddConsole();
  26. if (env.IsDevelopment())
  27. {
  28. app.UseDeveloperExceptionPage();
  29. }
  30. app.Use(async (context, next) =>
  31. {
  32. await context.Response.WriteAsync("Hello World!!");
  33. await next();
  34. });
  36. app.Run(async (context) =>
  37. {
  38. await context.Response.WriteAsync(" Welcome to Dotnet Core ");
  39. });
  41. }
  42. }
  43. }
Output 2
Reference
Conclusion
We learned how to Install .NET Core tools preview for Visual Studio and how to print “Hello World” in the latest ASP.NET Core 1.0.