unset

Unset a given variable

Syntax

unset ( mixed $var [, mixed $... ] ) : void

Parameters

var

The variable to be unset.

...

Another variable ...

Return

No value is returned.

Examples

1

<?

$var = 1;

unset($var);

var_dump($var);

?>
NULL

2

<?

$var1 = 1;
$var2 = 2;
$var3 = 3;

unset($var1, $var2, $var3);

var_dump($var1, $var2, $var3);

?>
NULL
NULL
NULL

3

<?

$var = array(0, 1, 2);

unset($var);

var_dump($var);

?>
NULL

4

<?

$var = array(0, 1, 2);

unset($var[1]);

print_r($var);

?>
Array
(
    [0] => 0
    [2] => 2
)

5

<?

$var = array("a" => 0, "b" => 1, "c" => 2);

unset($var["b"]);

print_r($var);

?>
Array
(
    [a] => 0
    [c] => 2
)

boolval

debug_zval_dump

doubleval

empty

floatval

get_debug_type

get_defined_vars

get_resource_id

get_resource_type

gettype

intval

is_array

is_bool

is_callable

is_countable

is_double

is_float

is_int

is_integer

is_iterable

is_long

is_null

is_numeric

is_object

is_real

is_resource

is_scalar

is_string

isset

print_r

serialize

settype

strval

unserialize

var_dump

var_export

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