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IteratorAggregate> <Iterator::rewind
[edit] Last updated: Sat, 25 May 2013

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Iterator::valid

(PHP 5 >= 5.0.0)

Iterator::validChecks if current position is valid

Description

abstract public boolean Iterator::valid ( void )

This method is called after Iterator::rewind() and Iterator::next() to check if the current position is valid.

Parameters

This function has no parameters.

Return Values

The return value will be casted to boolean and then evaluated. Returns TRUE on success or FALSE on failure.



IteratorAggregate> <Iterator::rewind
[edit] Last updated: Sat, 25 May 2013
 
add a note add a note User Contributed Notes Iterator::valid - [3 notes]
up
1
seva dot lapsha at gmail dot com
3 years ago
If Iterator::valid() returns false, the foreach() loop will be terminated.
up
0
Voitcus at gmail dot com
2 months ago
If your class implements also ArrayAccess interface, you could use as valid() body

function valid(){   
   return $this->offsetExists($this->position);
}
up
0
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)
?>

 
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