Predefined Constants
Examples
COM
PHP Manual

# Errors and error handling

Exceptions (PHP 5)

This extension will throw instances of the class com_exception whenever there is a potentially fatal error reported by COM. All COM exceptions have a well-defined code property that corresponds to the HRESULT return value from the various COM operations. You may use this code to make programmatic decisions on how to handle the exception.

Predefined Constants
Examples
COM
PHP Manual