Given the Name or ID of an McObjects Category, returns the corresponding ID or Name, respectively. The Category ID is the value returned by the RegisterCategory method.
If the varNameOrID is given as a name, that category name must be within the scope of the current default Namespace, unless the actual namespace is supplied via the :: syntax.
If an unknown category name is supplied, a category ID of zero is returned. If an illegal category ID is supplied, results are unpredictable and likely to result in program failure.