Countable::count
(PHP 5 >= 5.1.0, PHP 7)
Countable::count — オブジェクトの要素数を数える
説明
abstract public int Countable::count
( void
)
パラメータ
この関数にはパラメータはありません。
例
例1 Countable::count() の例
<?php
class myCounter implements Countable {
private $count = 0;
public function count() {
return ++$this->count;
}
}
$counter = new myCounter;
for($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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