The PHP documentation is not very explicit and only states that:
SplObjectStorage::offsetExists Checks whether an object exists in the storage. (PHP >= 5.3.0)
SplObjectStorage::contains Checks if the storage contains the object provided. (PHP >= 5.1.0)
Which pretty much seems the same thing to me.
QUESTION: Apart from offsetExists being only available in 5.3.0, what is the difference between the 2?
small test I conducted...
$s = new SplObjectStorage();
$o1 = new StdClass();
$o2 = new StdClass();
$o3 = "I'm not an object!";
$s->attach($o1);
var_dump($s->contains($o1));
var_dump($s->offsetExists($o1));
echo '<br>';
var_dump($s->contains($o2));
var_dump($s->offsetExists($o2));
echo '<br>';
var_dump($s->contains($o3));
var_dump($s->offsetExists($o3));
output:
boolean true
boolean true
boolean false
boolean false
Warning: SplObjectStorage::contains() expects parameter 1 to be object, string given in index.php on line 15
null
Warning: SplObjectStorage::offsetExists() expects parameter 1 to be object, string given in index.php on line 16
null