1.3 Choosing a Language

1.4 Why and When Would I Use ASP.NET?

You should use ASP.NET for any new projects you are about to start for the following reasons:

• Reduced development time

• Increased performance

• Increased application stability

• Increased scalability

• New ASP.NET features (see the discussion later in this chapter)

Some of these benefits, such as reduction in development time, assume familiarity with the .NET development platform. If you are starting your first ASP.NET development project, you should allow some time for getting up to speed on the new platform. Subsequent projects should see reduced development time over classic ASP, as developers become more familiar with the platform.

In addition to these factors, ASP.NET, like ASP, is available for free. The only costs associated with ASP.NET development are the costs of the operating system on which you wish to run your application (Windows 2000, Windows XP, or Windows Server 2003) and the cost of the development environment you choose to use. Of course, as with classic ASP, you can use free or inexpensive text editors to create your applications. Given that the .NET Framework is a free add-on to Windows (and is integrated with the Windows Server 2003 line), it is possible to create ASP.NET applications without spending a penny beyond the cost of the operating system and hardware on which it will run. Integrated development environments, such as Microsoft Visual Studio .NET 2003, are also available at an additional cost and greatly simplify ASP .NET development.

1.5 Why and When Would I Port an Existing Application to ASP.NET?

A trickier question is, "When will it be worthwhile to make the effort to migrate an existing application from ASP to ASP.NET?" The reality is that while classic ASP and ASP.NET have many common features, for most applications, it will not be a trivial task to migrate an application from one to the other. Changes in languages, as well as some changes in the way that ASP.NET operates compared to classic ASP, mean that depending on how your classic ASP application is structured, migration could require a significant amount of effort.

How do you decide whether a migration is worthwhile? If your application is in production, meets your needs functionally and in terms of performance and scalability, and you do not anticipate further development on the application, it's probably best to simply run it as a classic ASP application. One big plus of the ASP.NET architecture is that it runs side by side with classic ASP, so you don't have to migrate applications. Keep in mind, however, that while classic ASP and ASP.NET applications can run side by side, even in the same directory, they do not share Session and Application context. Thus, you will need to devise your own means of transferring any information you store in the Session or Application collections to and from ASP and ASP.NET, if you want to share that information between classic ASP and ASP.NET pages.

If your application is due for a new development cycle or revision, it's worth examining the types of functionality that your application uses and examining whether ASP.NET would be helpful in meeting the needs of the application. For example, if you have an application that struggles to meet your needs in terms of performance and scalability, the improved performance of the compiled-code model of ASP.NET and its new out-of-process Session State support may enable you to meet these goals easily.

What's important to consider is balancing the cost of migration against the benefits offered by migration. In this book, we will discuss the improvements and benefits offered by ASP.NET. It is left as an exercise for the reader to weigh these improvements against one another and determine whether to migrate a particular application.