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  • SimpleXMLIterator::valid()

    (PHP 5, PHP 7)

    Check whether the current element is valid

    说明

    publicSimpleXMLIterator::valid(void): bool

    This method checks if the current element is valid after calls to SimpleXMLIterator::rewind() or SimpleXMLIterator::next().

    参数

    此函数没有参数。

    返回值

    Returns TRUE if the current element is valid, otherwise FALSE

    范例

    Example #1 Check whether the current element is valid

    <?php
    $xmlIterator = new SimpleXMLIterator('<books><book>SQL Basics</book></books>');
    $xmlIterator->rewind(); // rewind to the first element
    echo var_dump($xmlIterator->valid()); // bool(true)
    $xmlIterator->next(); // advance to the next element
    echo var_dump($xmlIterator->valid()); // bool(false) because there is only one element
    ?>