ASP.NET simplifies developers’ transition from Windows application development to web development by offering the ability to build pages composed of controls similar to a Windows user interface. A web control, such as a button or label, functions in very much the same way as its Windows counterpart: code can assign its properties and respond to its events. Controls know how to render themselves: whereas Windows controls draw themselves to the screen, web controls produce segments of HTML and JavaScript which form parts of the resulting page sent to the end-user’s browser.
ASP.NET encourages the programmer to develop applications using an event-driven GUI model, rather than in conventional web-scripting environments like ASP and PHP. The framework combines existing technologies such as JavaScript with internal components like “ViewState” to bring persistent (inter-request) state to the inherently stateless web environment.
Other differences compared to ASP classic are:
Compiled code means applications run faster with more design-time errors trapped at the development stage.
Significantly improved run-time error handling, making use of exception handling using try-catch blocks.
Similar metaphors to Microsoft Windows applications such as controls and events.
An extensive set of controls and class libraries allows the rapid building of applications, plus user-defined controls allow commonly-used web template, such as menus. Layout of these controls on a page is easier because most of it can be done visually in most editors.
ASP.NET uses the multi-language abilities of the .NET Common Language Runtime, allowing web pages to be coded in VB.NET, C#, J#, Delphi.NET, Chrome, etc.
Ability to cache the whole page or just parts of it to improve performance.
Ability to use the code-behind development model to separate business logic from presentation.
Ability to use true object-oriented design for programming pages and controls
If an ASP.NET application leaks memory, the ASP.NET runtime unloads the AppDomain hosting the erring application and reloads the application in a new AppDomain.
Session state in ASP.NET can be saved in a Microsoft SQL Server database or in a separate process running on the same machine as the web server or on a different machine. That way session values are not lost when the web server is reset or the ASP.NET worker process is recycled.
