Razor Pages is a new feature of ASP.NET Core MVC that makes coding page-focused scenarios easier and more productive.

Razor Pages requires ASP.NET Core 2.0.0 or later. Tooling support for Razor Pages ships in Visual Studio 2017 Update 3 or later. 

WebSocket is real-time communication protocol we can use to make UI in browser to send and receive messages from server over real-time communication channel. WebSocket is also supported by ASP.NET Core. This blog post demonstrates how to build simple browser based chat room on ASP.NET Core and WebSocket. 

Change this section ...

  <PropertyGroup>
    <TargetFramework>netcoreapp2.2</TargetFramework>
    <AspNetCoreHostingModel>InProcess</AspNetCoreHostingModel>
  </PropertyGroup>

to the following ...

  <PropertyGroup>
    <TargetFramework>netcoreapp2.2</TargetFramework>
    <AspNetCoreHostingModel>OutOfProcess</AspNetCoreHostingModel>
    <AspNetCoreModuleName>AspNetCoreModule</AspNetCoreModuleName>
  </PropertyGroup>

Performance Improvements in .NET Core 

Discontinued Technology in .NET Core 

    public class HomeController : Controller
    {
        public IActionResult GetFile()
        {
            return PhysicalFile(@"C:\path\file.pdf", "application/pdf");
        }

Partial Views and Child Actions are one the most used features of ASP.NET MVC. Partial Views provides us a way to create a reusable component that can be used in multiple Views. There are Actions which can be marked as Child Actions and these cannot be invoked via URL but inside views or partial views. Child Actions are no more available with ASP.NET Core. View Components are new way to implement this feature in ASP.NET Core.