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    ArrayIterator::append

    (PHP 5, PHP 7, PHP 8)

    ArrayIterator::append — 要素を追加する

    説明

    public ArrayIterator::append(mixed $value): void

    値を最後の要素として追加します。

    警告

    この関数は、 現在のところ詳細な情報はありません。引数のリストのみが 記述されています。

    パラメータ

    value

    追加する値。

    戻り値

    値を返しません。

    注意

    注意:

    このメソッドは、ArrayIterator がオブジェクトを参照している場合はコールできません。

    参考

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    User Contributed Notes 2 notes

    up
    3
    martin dot abbrent+php dot net at ufz dot de
    11 years ago
    As ArrayIterator is not a real list the implementation of "append" is a little bit confusing me. When using "append" I expected the new value at the postion "last element index + 1". This will not happen when you unset elements before.
    It seems like indexes once they're used are blacklisted end never used again, even if they're unset.
    Like suggested in http://www.php.net/manual/de/arrayiterator.offsetset.php#106775 ArrayIterator::append uses ArrayIterator::offsetSet with empty index parameter. So I've this two workarounds to get "append" to work like I want:

    <?php
    class myArrayIterator extends ArrayIterator {

    public function     offsetSet($offset, $value) {

    if (    is_null($offset)) { // offset == null when it's called by ArrayIterator::append
    $offset = $this->generateOffset(); // do it in a separate method
    }
    parent::offsetSet($offset, $value); // call the native implementation with an index
    $this->ksort(); // sort it to avoid confusion when it gets dumped or iterated
    }

    protected function     generateOffset() {

    $offset = count($this); // take count as offset as it should be lastKey+1
    while ($this->offsetExists($offset)) { // is it really empty?
    $offset++; // try the next one until there's an empty one
    }
    return     $offset;
    }
    }

    class     mySaveArrayIterator extends myArrayIterator {

    protected function     generateOffset() {

    $offset = 0; // expect zero is the first possible key
    while ($this->offsetExists($offset)) { // try every key until there's an empty one
    $offset++;
    }
    return     $offset;
    }
    }

    $data = array('foo', 'bar', 'baz');

    $array = new ArrayIterator($data);
    $myArray = new myArrayIterator($data);
    $mySaveArray = new mySaveArrayIterator($data);

    // remove the last element
    $array ->offsetUnset(2);
    $myArray ->offsetUnset(2);
    $mySaveArray->offsetUnset(2);

    // append an element
    $array ->append('foobar');
    $myArray ->append('foobar');
    $mySaveArray->append('foobar');

    // check the position of the new element
    print_r($array);
    print_r($myArray);
    print_r($mySaveArray);

    // remove some element
    $array ->offsetUnset(1);
    $myArray ->offsetUnset(1);
    $mySaveArray->offsetUnset(1);

    // again append an element
    $array ->append('foobarbaz');
    $myArray ->append('foobarbaz');
    $mySaveArray->append('foobarbaz');

    // check the position of the new element
    print_r($array);
    print_r($myArray);
    print_r($mySaveArray);
    ?>

    Output:

    ArrayIterator Object
    (
    [storage:ArrayIterator:private] => Array
    (
    [0] => foo
    [1] => bar
    [3] => foobar
    )

    )
    myArrayIterator Object
    (
    [storage:ArrayIterator:private] => Array
    (
    [0] => foo
    [1] => bar
    [2] => foobar
    )

    )
    mySaveArrayIterator Object
    (
    [storage:ArrayIterator:private] => Array
    (
    [0] => foo
    [1] => bar
    [2] => foobar
    )

    )
    ArrayIterator Object
    (
    [storage:ArrayIterator:private] => Array
    (
    [0] => foo
    [3] => foobar
    [4] => foobarbaz
    )

    )
    myArrayIterator Object
    (
    [storage:ArrayIterator:private] => Array
    (
    [0] => foo
    [2] => foobar
    [3] => foobarbaz
    )

    )
    mySaveArrayIterator Object
    (
    [storage:ArrayIterator:private] => Array
    (
    [0] => foo
    [1] => foobarbaz
    [2] => foobar
    )

    )

    This helped me to treat the ArrayIterator as a list with valid indexes in a serial manner.
    up
    -1
    lenye01 at gmail dot com
    13 years ago
    we can append values after the given array,the index is begin from 0, for example:

    <?php
    $b     = array('name'=>'mengzhi','age'=>'22','city'=>'shanghai');
    $a = new ArrayIterator($b);
    $a->append(array('home'=>'china','work'=>'developer'));
    var_dump($a);
    ?>

    then output:
    object(ArrayIterator)#1 (1) { ["storage":"ArrayIterator":private]=> array(4) { ["name"]=> string(7) "mengzhi" ["age"]=> string(2) "12" ["city"]=> string(8) "shanghai" [0]=> array(2) { ["home"]=> string(5) "china" ["work"]=> string(9) "developer" } } }
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