ASP.Net Programming Environment

ASP.NET has a rich set of software objects to work with in an object-oriented and compiled programming environment. Much of the functionality takes place in the background with details hidden from view of, and usually hidden from concern by, the programmer. All built-in software objects have easy-to-use programming interfaces permitting you to perform elaborate or complex processing with simple and straight-forward code.

Under ASP.NET 2.0 the programming environment takes on the feel of declarative programming rather than conventional logical programming. That is, programs, or scripts, are descriptions of what processing to perform more so than how to perform it. Traditional programming requires exacting, detailed instructions on the sequence of processing steps a computer performs to generate its output. Under ASP.NET 2.0 these processing steps are largely encapsulated within available software objects. The programming task becomes one of selecting appropriate objects and requesting their properties and methods to return expected results. The details about how this processing takes place is of little concern.

It is for this reason that "programming" become "scripting" under ASP.NET. The programmer works with a higher-level set of instructions to carry out processing. Detailed programming logic is replaced by requests for services. The programmer simply declares what processing is needed; ASP.NET returns the results. The hard work of programming is prepackaged inside the components that are called.

The programming environment supports more than 25 .NET languages, including built-in support for VB.NET, C#, and JScript.NET. In this tutorial all server code is implement in Visual Basic (VB.NET). As a fully object-oriented environment, the .NET Framework offers over 4500 software classes that encapsulate rich functionality like XML, data access, file upload, regular expressions, image generation, performance monitoring and logging, transactions, SMTP mail, and much more. These classes provide an extensive set of objects, properties, and methods accessible through Visual Basic to enhance your Web applications.

All of the processing functionality of VB.NET is built into ASP.NET. The primary difference in the two environments is in how input and output activities are performed. User interaction under ASP.NET is, of course, through a Web browser. Therefore, some of the form controls you may have used under VB.NET do not have ASP.NET equivalents. Still, new Web Form controls in ASP.NET that replace many of the standard HTML tags bring the two environments closer together. As both environments are further developed there is likely to be convergence of the two technologies into one. Applications development for the desktop and for the Web will be virtually indistinguishable.

Though code is compiled, ASP.NET automatically detects any code changes, dynamically compiles the files if needed, and stores the compiled results for reuse in subsequent requests. Dynamic compilation ensures that applications are up to date, and compiled execution makes them fast. There is a short delay when a page is first accessed and compiled. Subsequent accesses, though, retrieve the compiled, cached version of the page for immediate execution.