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.
An array or Countable object.
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.
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.
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 array_or_countable is
NULL,
0 will be returned.
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
?>
| Version | Description |
|---|---|
| 4.2.0 |
The optional mode parameter was added.
|
