PHP: count function - Count elements in an array, or properties in an object

Description

int count ( mixed $var [, int $mode ] )

Counts elements in an array, or properties in an object.

For objects, if you have SPL installed, you can hook into count() by implementing interface Countable. The interface has exactly one method, count(), which returns the return value for the count() function.

Please see the Array section of the manual for a detailed explanation of how arrays are implemented and used in PHP.

Parameters

var: The array.
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. The default value for mode is 0. count() does not detect infinite recursion.

Return Values

Returns the number of elements in var , which is typically an array, since anything else will have one element.

If var is not an array or an object with implemented Countable interface, 1 will be returned. There is one exception, if var is NULL, 0 will be returned.

Caution

count() may return 0 for a variable that isn't set, but it may also return 0 for a variable that has been initialized with an empty array. Use isset() to test if a variable is set.

ChangeLog

Version	Description
4.2.0	The optional `mode` parameter was added.

Examples

Example #1 count() example


<?php
$a[0] = 1;
$a[1] = 3;
$a[2] = 5;
$result = count($a);
// $result == 3

$b[0]  = 7;
$b[5]  = 9;
$b[10] = 11;
$result = count($b);
// $result == 3

$result = count(null);
// $result == 0

$result = count(false);
// $result == 1
?>

Example #2 Recursive count() example


<?php
$food = array('fruits' => array('orange', 'banana', 'apple'),
              'veggie' => array('carrot', 'collard', 'pea'));

// recursive count
echo count($food, COUNT_RECURSIVE); // output 8

// normal count
echo count($food); // output 2

?>

count

Description

Parameters

Return Values

ChangeLog

Examples

See Also