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    Countable::count

    (PHP 5 >= 5.1.0, PHP 7, PHP 8)

    Countable::count — Count elements of an object

    説明

    public Countable::count(): int

    This method is executed when the value for count() is an object implementing Countable.

    パラメータ

    この関数にはパラメータはありません。

    戻り値

    The custom count as an int.

    例

    例1 Countable::count() example

    <?php

    class Counter implements Countable
    {
    private     $count = 0;

    public function     count(): int
    {
    return ++    $this->count;
    }
    }

    $counter = new Counter;

    for (    $i = 0; $i < 10; ++$i) {
    echo     "I have been count()ed " . count($counter) . " times\n";
    }

    ?>

    上の例の出力は、 たとえば以下のようになります。

    I have been count()ed 1 times
I have been count()ed 2 times
I have been count()ed 3 times
I have been count()ed 4 times
I have been count()ed 5 times
I have been count()ed 6 times
I have been count()ed 7 times
I have been count()ed 8 times
I have been count()ed 9 times
I have been count()ed 10 times

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    User Contributed Notes 1 note

    up
    13
    SenseException
    10 years ago
    Even though Countable::count method is called when the object implementing Countable is used in count() function, the second parameter of count, $mode, has no influence to your class method.

    $mode is not passed to Countable::count:

    <?php

    class Foo implements Countable
    {
    public function     count()
    {
    var_dump(func_get_args());
    return     1;
    }
    }

    count(new Foo(), COUNT_RECURSIVE);

    ?>

    var_dump output:

    array(0) {
    }
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