ASP in a Nutshell, 2nd Edition

Chapter 4. Application Object

In the context of Active Server Pages, an application is the sum of all the files that can be accessed through a given virtual directory and its subdirectories. This ASP application context is the same for all clients using the application. For example, a client from Thailand who requests pages from your /SearchApp virtual directory is accessing the same "application" as a second client from Sweden who is requesting pages from the same virtual directory—regardless of which specific web page within the virtual directory each is requesting.

Just as traditional standalone applications allow you to share information throughout the application, so too do ASP applications. You can share information among all clients of a given ASP application using the Application object. This built-in object represents the ASP application itself and is the same regardless of the number or type of clients accessing the application and regardless of what part or parts of the application those clients are requesting.

The Application object is initialized by IIS the moment the first client requests any file from within the given virtual directory. It remains in the server's memory until either the web service is stopped or the application is explicitly unloaded from the web server using the Microsoft Management Console.

IIS allows you to instantiate variables and objects with application-level scope. This means that a given variable contains the same value for all clients of your ...