Over Use of constants.... in OOP

[LixoTen]

Am new to PHP, and OOP but....

Is it possible to over use Constants? 

const = "77";

define("CONTACT_URL", "localhost/contact.html?");

Specially in OOP?.... 

What about something like current Customer ID, status, current loaded URL? .... I changes from Page load to page load but it is constant during a page load

These things are retrieves and validated at very start of a page load. I am just wondering why I don't see more scrips with Constants

[administrator]

You can use constants for sure. Why don't you see them used often? Probably because their advantage in most circumstances are not obvious.

Stef