Developing Web Applications

Microsoft Script Debugger

You can use Script Debugger to test scripts written in VBScript and JScript, as well as applications written in Java. You can also debug scripts in other languages that support host-independent debugging, such as REXX or PerlScript.

Using Script Debugger, you can:

View the source code of the script you are debugging.
Control execution line by line through the script.
View and alter variable and property values.
Set breakpoints and view the call stack.
Switch between threads of execution.

You can use Script Debugger to debug both client-side and server-side scripts. Debugging must be enabled for each ASP application that you want to debug.

To enable debugging

In Internet Services Manager, right-click an application virtual directory and click Properties.
On the Virtual Directory tab, click Configuration.
On the App Debugging tab, select Enable ASP server-side script debugging and click OK.

To begin editing a document in Script Debugger, first open the Running Documents window (from the View menu) and double-click to open a document. Before you can open the script, it must be loaded locally in the browser, or in the ASP environment on the local Web server, if one is installed. Once the script is loaded, you can set breakpoints, and step through the application.

You can view and change the values of individual variables in the Command window when a script is running. To view a variable value, type a question mark (?) followed by the name of the variable, and press Enter. You can also evaluate simple numeric expressions using the “?” command form. To edit the value, type the name of the variable followed by an equal sign (=) and a new numeric or string value.

Since Script Debugger only works with scripts running on the local Web server, you cannot debug scripts running on remote Web servers. Because the script debugger interrupts script execution when it encounters an error, you won’t want to enable script debugging on systems that are hosting applications critical to your business. For these systems, it is better to trace execution by using logs and output.

For more information about Script Debugger, see the IIS 5.0 online product documentation.