Scott's example is documented very well and can be seen in four parts: ASP.NET MVC Framework (Part 1) ASP.NET MVC Framework (Part 2): URL Routing ...

Page methods communicate directly with an ASP.NET AJAX-enabled page and pass JSON request and response messages back and forth, just as WebMethods do in Web services. The code below shows an example ...

Click Create. In the “Create New ASP.Net Core Web Application” window shown next, select .Net Core as the runtime and ASP.Net Core 2.2 (or later) from the drop-down menu at the top.