Iterator::rewind
If Iterator::valid() returns false, the foreach() loop will be terminated.
Iterator::valid
(PHP 5 >= 5.0.0)
Iterator::valid — Checks if current position is valid
Descrizione
abstract public boolean Iterator::valid
( void
)
This method is called after Iterator::rewind() and Iterator::next() to check if the current position is valid.
Elenco dei parametri
Questa funzione non contiene parametri.
Valori restituiti
The return value will be casted to boolean and then evaluated.
Restituisce TRUE in caso di successo, FALSE in caso di fallimento.
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User Contributed Notes
Iterator::valid - [3 notes]
seva dot lapsha at gmail dot com ¶
3 years ago
Voitcus at gmail dot com ¶
1 month ago
If your class implements also ArrayAccess interface, you could use as valid() body
function valid(){
return $this->offsetExists($this->position);
}
hyponiq at gmail dot com ¶
1 year ago
Take consideration when utilizing this method and using the returned value of isset([value]). The value of isset([value]) will be false for null values.
I ran into this problem when checking isset([value]) against array elements whose value was null.
Example:
<?php
$array = array(null, 1, 2, 3);
$isSet = isset($array[0]);
var_dump($isSet); // output: boolean(false)
class AClass {
public $array = (null, 1, 2, 3);
function valid() {
return isset($this->array[0]);
}
}
$class = new AClass;
var_dump($class->valid()); // output: boolean(false)
?>