count
Counts all elements in an array or in a Countable object
Description
int count(Countablearray $value, int $mode = COUNT_NORMAL)
Parameters
-
value
-
An array or Countable object.
-
mode
-
If the optional mode parameter is set to
COUNT_RECURSIVE (or 1), count
will recursively count the array. This is particularly useful for
counting all the elements of a multidimensional array.
Caution
count can detect recursion to avoid an infinite
loop, but will emit an E_WARNING every time it
does (in case the array contains itself more than once) and return a
count higher than may be expected.
Return Values
Returns the number of elements in value.
Prior to PHP 8.0.0, if the parameter was neither an array nor an object that
implements the Countable interface,
1 would be returned,
unless value was null, in which case
0 would be returned.
Examples
Example #1 count example
<?php
$a[0] = 1;
$a[1] = 3;
$a[2] = 5;
var_dump(count($a));
$b[0] = 7;
$b[5] = 9;
$b[10] = 11;
var_dump(count($b));
?>
The above example will output:
Example #2 count non Countable|array example (bad example - don't do this)
<?php
$b[0] = 7;
$b[5] = 9;
$b[10] = 11;
var_dump(count($b));
var_dump(count(null));
var_dump(count(false));
?>
The above example will output:
int(3)
Fatal error: Uncaught TypeError: count(): Argument #1 ($var) must be of type Countable .. on line 12
Example #3 Recursive count example
<?php
$food = array('fruits' => array('orange', 'banana', 'apple'),
'veggie' => array('carrot', 'collard', 'pea'));
// recursive count
var_dump(count($food, COUNT_RECURSIVE));
// normal count
var_dump(count($food));
?>
The above example will output:
Example #4 Countable object
<?php
class CountOfMethods implements Countable
{
private function someMethod()
{
}
public function count(): int
{
return count(get_class_methods($this));
}
}
$obj = new CountOfMethods();
var_dump(count($obj));
?>
The above example will output:
See Also
- is_array
- isset
- empty
- strlen
- is_countable
- Arrays