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    RecursiveArrayIterator::hasChildren

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

    RecursiveArrayIterator::hasChildren — 現在のエントリが配列あるいはオブジェクトであるかどうかを返す

    説明

    public RecursiveArrayIterator::hasChildren(): bool

    現在のエントリが配列あるいはオブジェクトであるかどうか、つまり RecursiveArrayIterator::getChildren() でイテレータを取得できるかどうかを返します。

    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

    現在のエントリが配列あるいはオブジェクトである場合に true、 それ以外の場合に false を返します。

    例

    例1 RecursiveArrayIterator::hasChildren() の例

    <?php
    $fruits     = array("a" => "lemon", "b" => "orange", array("a" => "apple", "p" => "pear"));

    $iterator = new RecursiveArrayIterator($fruits);

    while (    $iterator->valid()) {

    // 子を持つかどうかを調べます
    if ($iterator->hasChildren()) {
    // すべての子を表示します
    foreach ($iterator->getChildren() as $key => $value) {
    echo     $key . ' : ' . $value . "\n";
    }
    } else {
    echo     "No children.\n";
    }

    $iterator->next();
    }
    ?>

    上の例の出力は以下となります。

    No children.
No children.
a : apple
p : pear

    参考

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    User Contributed Notes 1 note

    up
    1
    Dominik
    9 years ago
    hasChildren() works as documented here, but not as its name suggests.

    The method does not return whether the current entry actually *has* children. It only returns whether the element's type is one that is able to have children.

    This is a bit counterintuitive if you are processing empty arrays.

    Example:

    <?php
    $data     = array(
    "element one" => array(true),
    "element two" => array(),
    "element three" => array(true),
    );

    $i = new RecursiveIteratorIterator(new RecursiveArrayIterator($data),RecursiveIteratorIterator::SELF_FIRST);

    foreach(    $i as $key => $value)
    {
    $type = gettype($value);
    $depth = $i->getDepth();

    if(    $i->hasChildren()) {
    echo     "$depth: $key ($type) has children\n";
    } else {
    echo     "$depth: $key ($type) has no children\n";
    }
    }
    ?>

    Result:

    0: element one (array) has children
    1: 0 (boolean) has no children
    0: element two (array) has children
    0: element three (array) has children
    1: 0 (boolean) has no children
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