int count(mixed $array_or_countable[, int $mode = COUNT_NORMAL])
Counts all elements in an array, or something 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, Countable::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.
Returns the number of elements in
array_or_countable. If the parameter is not an array or not an object with implemented Countable interface, 1 will be returned. There is one exception, if
NULL, 0 will be returned.
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.
- mixed $array_or_countable: An array or Countable object.
- int $mode [ = COUNT_NORMAL]: If the optional
modeparameter 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_WARNINGevery time it does (in case the array contains itself more than once) and return a count higher than may be expected.
Example #1 count() example
$a = 1;
$a = 3;
$a = 5;
$result = count($a);
// $result == 3
$b = 7;
$b = 9;
$b = 11;
$result = count($b);
// $result == 3
$result = count(null);
// $result == 0
$result = count(false);
// $result == 1
Example #2 Recursive count() example
$food = array('fruits' => array('orange', 'banana', 'apple'),
'veggie' => array('carrot', 'collard', 'pea'));
// recursive count
echo count($food, COUNT_RECURSIVE); // output 8
// normal count
echo count($food); // output 2