SimpleXMLIterator::valid
(PHP 5 >= 5.1.0, PHP 7)
SimpleXMLIterator :: valid - 检查当前元素是否有效
描述
public bool SimpleXMLIterator::valid ( void )
此方法在调用SimpleXMLIterator :: rewind()或SimpleXMLIterator :: next()之后检查当前元素是否有效。
参数
该功能没有参数。
返回值
如果当前元素有效,则返回TRUE,否则返回FALSE
例子
Example#1 检查当前元素是否有效
<?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
?>
← SimpleXMLIterator::rewind
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