SimpleXMLIterator::valid

(PHP 5, PHP 7)

SimpleXMLIterator::valid — Check whether the current element is valid

说明

public SimpleXMLIterator::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
?>

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