Debugging a Global.asa File

Debugging a Global.asa differs from debugging .asp files.

You cannot request a Global.asa file specifically in the client browser. Instead, the server executes its procedures automatically when first you request other files in the ASP-based application. Therefore, you cannot use a browser command to start the debugger.
Procedures in a Global.asa file are event-driven, unlike procedures in .asp files.
Procedures in a Global.asa file usually run only once per application or once per session:
- The Application_OnStart procedure executes the first time that any user accesses any page in an ASP-based application.
- The Application_OnEnd procedure executes only when the application is shut down.
- The Session_OnStart procedure executes only once per user session.
- The Session_OnEnd procedure executes only when a user’s session times out or when a script explicitly calls the Session object’s Abandon method.

If there is an error in a Global.asa file (either a syntax error or runtime error), the server stops the procedure containing the error. If the Script Debugger is enabled for that ASP application, the server starts the debugger and displays an error message. If the Script Debugger is not enabled for the ASP application, an error message is sent to the client browser. In either case, the procedure containing the error stops. When you fix the error in a Global.asa file and request a page from the application again, the procedures in a Global.asa are executed again when the ASP application is restarted — a Global.asa file is executed again whenever you make a change in it and save it.

To control when the Script Debugger is called from a Global.asa file, include a statement that starts the debugger explicitly, such as Stop in VBScript or debugger in JScript. Place the statement at the beginning of the procedure, before any statements that you will want to step through.

When the application starts or when a user starts a new session, the corresponding procedure in a Global.asa file will run. The Script Debugger will start when the Stop or debugger statement is executed. You can then step through the procedure normally, use the Command window to evaluate expressions and set values, and so on.

However, you cannot stop and restart the script by refreshing a Global.asa file. If you want to rerun the Application_OnStart event procedure, you must stop the application and then restart it. If you want to rerun the Session_OnStart event procedure, you can restart your browser, which starts a new session and reruns the Session_OnStart event procedure. Alternatively, you can request a page that includes a script to call the Session object’s Abandon method, and then start a new session.