Comparing objects in PHP 5
Warning
This extension is EXPERIMENTAL. The behaviour of this extension
-- including the names of its functions and anything else
documented about this extension -- may change without notice
in a future release of PHP. Use this extension at your own
risk.
In PHP 5, object comparison is a more complicated than
in PHP 4 and more in accordance to what one will expect
from an Object Oriented Language (not that PHP 5 is such
a language).
When using the comparison operator (==), object variables
are compared in a simple manner, namely: Two object instances
are equal if they have the same attributes and values, and
are instances of the same class.
On the other hand, when using the identity operator (===),
object variables are identical if and only if they refer
to the same instance of the same class.
An example will clarify these rules.
|