The toString method will print out several components:

• The file, line, static message, and object class name from the constructor. You can access these independently with the members file, line, msg, and printableExceptionName.
• The generic category codes stored with this exception
• Additional members stored with the exception child classes (e.g. platform error codes, associated function arguments)
• The stack trace associated with the exception. You can access these lines independently with foreach over the info member.

This is meant to be read by the developer, not end users. You should wrap your user-relevant tasks in a try/catch block and construct more appropriate error messages from context available there, using the individual properties of the exception to add richness.