ASP.NET Web API

ASP.NET is an open-sourceserver-side web application framework designed for web development to produce dynamic web pages. It was developed by Microsoft to allow programmers to build dynamic web sites, web applications and web services.

It was first released in January 2002 with version 1.0 of the .NET Framework, and is the successor to Microsoft's Active Server Pages (ASP) technology. ASP.NET is built on the Common Language Runtime (CLR), allowing programmers to write ASP.NET code using any supported .NET language. The ASP.NET SOAP extension framework allows ASP.NET components to process SOAP messages.

ASP.NET's successor is ASP.NET Core. It is a re-implementation of ASP.NET as a modular web framework, together with other frameworks like Entity Framework. The new framework uses the new open-source .NET Compiler Platform (codename "Roslyn") and is cross platform. ASP.NET MVC, ASP.NET Web API, and ASP.NET Web Pages (a platform using only Razor pages) have merged into a unified MVC 6.

ASP.NET Web pages, known officially as Web Forms, are the main building blocks for application development in ASP.NET. There are two basic methodologies for Web Forms, a web application format and a web site format. Web applications need to be compiled before deployment, while web sites structures allows the user to copy the files directly to the server without prior compilation. Web forms are contained in files with a ".aspx" extension; these files typically contain static (X)HTML markup or component markup. The component markup can include server-side Web Controls and User Controls that have been defined in the framework or the web page. For example, a textbox component can be defined on a page as <asp:textbox id='myid' runat='server'>, which is rendered into a html input box. Additionally, dynamic code, which runs on the server, can be placed in a page within a block <% -- dynamic code -- %>, which is similar to other Web development technologies such as PHP, JSP, and ASP. With ASP.NET Framework 2.0, Microsoft introduced a new code-behind model that lets static text remain on the .aspx page, while dynamic code remains in an .aspx.vb or .aspx.cs or .aspx.fs file (depending on the programming language used).