(PHP 5 >= 5.0.0)
ArrayObject::offsetGet — Returns the value at the specified index
index
     The index with the value.
   The value at the specified index or NULL.
  
   Produces an E_NOTICE error message when the specified
   index does not exist.
  
Example #1 ArrayObject::offsetGet() example
<?php
$arrayobj = new ArrayObject(array('zero', 7, 'example'=>'e.g.'));
var_dump($arrayobj->offsetGet(1));
var_dump($arrayobj->offsetGet('example'));
var_dump($arrayobj->offsetExists('notfound'));
?>
The above example will output:
int(7) string(4) "e.g." bool(false)