note 101038 modified in splfixedarray.offsetunset by danbrown
| From: | danbrown@php.net | Date: | Mon, 22 Nov 2010 16:08:55 +0000 |
| Subject: | note 101038 modified in splfixedarray.offsetunset by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-174261@lists.php.net to get a copy of this message | ||
This function assigns NULL to the array element. Its use has no effect on count(). Whereas assigning
NULL to an element will have no effect on isset(), offsetUnset() and unset() do. Whereas unsetting
an element affects the behaviour of foreach() as applied to an array or an ArrayObject, it has no
such effect on SplFixedArray, as demonstrated by the code below.
<?php
class atest extends SplFixedArray {
public function fill() {
for ($i = $this->count(); --$i >= 0; ) $this[$i] = $i;
}
public function dump() {
$sep = ' ';
foreach ($this as $k => $v) {
echo $sep, "$k: ", (is_null($v) ? 'NULL' : $v);
if (!isset($this[$k])) echo ' and unset';
$sep = ', ';
}
echo PHP_EOL;
}
}
$a = new atest(3);
$a->dump(); // 0: NULL and unset, 1: NULL and unset, 2: NULL and unset
$a->fill();
$a->dump(); // 0: 0, 1: 1, 2: 2
$a[1] = NULL;
unset($a[2]);
$a->dump(); // 0: 0, 1: NULL, 2: NULL and unset
?>
--was--
This function assigns NULL to the array element. Its use has no effect on count(). Whereas assigning
NULL to an element will have no effect on isset(), offsetUnset() and unset() do. Whereas unsetting
an element affects the behaviour of foreach() as applied to an array or an ArrayObject, it has no
such effect on SplFixedArray, as demonstrated by the code below.
<?php
class atest extends SplFixedArray {
public function fill() {
for ($i = $this->count(); --$i >= 0; ) $this[$i] = $i;
}
public function dump() {
$sep = ' ';
foreach ($this as $k => $v) {
echo $sep, "$k: ", (is_null($v) ? 'NULL' : $v);
if (!isset($this[$k])) echo ' and unset';
$sep = ', ';
}
echo PHP_EOL;
}
}
$a = new atest(3);
$a->dump(); // 0: NULL and unset, 1: NULL and unset, 2: NULL and unset
$a->fill();
$a->dump(); // 0: 0, 1: 1, 2: 2
$a[1] = NULL;
unset($a[2]);
$a->dump(); // 0: 0, 1: NULL, 2: NULL and unset
http://php.net/manual/en/splfixedarray.offsetunset.php