(PHP 5 >= 5.3.0, PHP 7, PHP 8)
SplFixedArray::offsetUnset — Unsets the value at the specified $index
Unsets the value at the specified index.
index
The index being unset.
No value is returned.
Throws
RuntimeException
when
index
is outside
the defined sice of the array or when
index
cannot be parsed as an integuer.
This function assigns NULL to the array element. Its use has no effect on count(). Whereas assigning NULL to an element will have no effect on isset(), offsetUnset() and unset() do. Whereas unsetting an element affects the behaviour of foreach() as applied to an array or an ArrayObject, it has no such effect on SplFixedArray, as demonstrated by the code below.<?php
classatestextendsSplFixedArray{
public function fill() {
for ($i= $this->count(); --$i>= 0; ) $this[$i] = $i;
}
public function dump() {
$sep= ' ';
foreach ($thisas$c=> $v) {
echo$sep, "$c: ", (is_null($v) ? 'NULL' : $v);
if (!isset($this[$c])) 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?>