PHP 7.0.6 Released

    The Countable interface

    (PHP 5 >= 5.1.0, PHP 7)

    Introduction

    Classes implementing Countable can be used with the count() function.

    Interface synopsis

    Countable {
    /* Methods */
    abstract public int count ( void )
    }

    Table of Contents

    User Contributed Notes

    isaac dot z dot foster dot nada at spamporfav dot gmail dot com
    5 years ago
    I just want to point out that your class has to actually implement the Countable interface, not just define a count method, to be able to use count($object) and get the expected results. I.e. the first example below won't work as expected, the second will. (The normal arrow function accessor ($object->count()) will work fine, but that's not the kewl part :) )

    <?php
    //Example One, BAD :(

    class CountMe
    {

        protected     $_myCount = 3;

        public function     count()
        {
            return     $this->_myCount;
        }

    }

    $countable = new CountMe();
    echo     count($countable); //result is "1", not as expected

    //Example Two, GOOD :)

    class CountMe implements Countable
    {

        protected     $_myCount = 3;

        public function     count()
        {
            return     $this->_myCount;
        }

    }

    $countable = new CountMe();
    echo     count($countable); //result is "3" as expected
    ?>
    Anonymous
    5 years ago
    Note that arrays don't implement countable. Therefore you can't force a countable parameter for a function if you want it also to work with native arrays.
    To Top