PHP in a Nutshell

Name

array_filter()

Synopsis

    array array_filter ( array arr [, function callback] )

The array_filter() allows you to filter elements through a function you specify. If the function returns true, the item makes it into the array that is returned; otherwise, it does not. For example:

    function endswithy($value) {
            return (substr($value, -1) =  = 'y');
    }

    $people = array("Johnny", "Timmy", "Bobby", "Sam", "Tammy", "Joe");
    $withy = array_filter($people, "endswithy");
    var_dump($withy);
    // contains "Johnny", "Timmy", "Bobby", and "Tammy"

In this script, we have an array of people, most of whom have a name ending with "y". However, several do not, and we want to have a list of people whose names ends in "y", so array_filter() is used. The function endswithy() will return true if the last letter of each array value is a "y"; otherwise, it will return false. By passing that as the second parameter to array_filter(), it will be called once for every array element, passing in the value of the element as the parameter to endswithy(), where it is checked for a "y" at the end.