ASP.NET provides a programming model and infrastructure that offers the necessary services for programmers to develop web-based applications. Because ASP.NET is part of the .NET Framework, programmers can use the managed Common Language Runtime (CLR) environment, type safety, inheritance, etc. to create web-based applications. You can develop your ASP.NET web-based applications in any .NET-compliant language, such as Visual Basic, Visual C#, or JScript.NET. ASP.NET code is compiled rather than interpreted, which permits early binding, strong typing, and just-in-time (JIT) compiling to native code.
In ASP.NET, deployment is as simple as copying a component assembly to its desired location. ASP.NET configuration settings are stored in XML-based files, which are human-readable and -writable. ASP.NET automatically applies new configuration settings to web resources whenever it finds any changes to configuration files, without rebooting the server.
There are two core programming models when developing an ASP.NET application:
· Web forms
· Web Services
Web forms allow you to develop programmable forms-based web pages. A web forms page consists of two parts:
· Visual elements: HTML elements and web forms controls.
· User interface logic: Code that contains logic for interacting with the visual elements.
In ASP.NET, business logic code (functional code) is separated from presentation code (HTML code). The visual elements are created in an .aspx file. The code is in a separate class file, called the code-behind class file (.aspx.vb or .aspx.cs), which consists of event handlers, initialization code, and other supporting code for the user interface in the aspx file.
Web services provide the capability to exchange messages in a loosely coupled environment using standard data formats and protocols such as HTTP, XML, and SOAP. A web service is nothing but a programmable application component that provides some serviceable, useful functionality such as application logic, and is available to any number of potentially incongruent systems through the use of Internet standards such as XML and HTTP.
ASP.NET provides solutions to some of the drawbacks that exist in ASP and offers a lot of additional benefits such as performance, scalability, deployment, security, output cache control, and web services infrastructure. Both ASP.NET and ASP run agreeably on an Internet Information Services (IIS) web server without interruption. Newly created ASP.NET pages with the file extension .aspx won't corrupt any existing ASP application. Files with an .aspx extension are processed by the ASP.NET runtime and files with an .asp extension are processed as usual by the ASP engine. ASP.NET offers total syntax and processing compatibility with ASP applications. The two systems have completely separate processing engines.