PHP中XPATH 实现xml及html文件快速解析（附xml做小型数据库实现六级单词快速查询实例）

一、XPATH简单入门

XPATH ，XQUERY 专门查询XML语言，查询速度快

使用方法：

（1）创建DOM工具，并且加载 xml文件

$xml = new DOMDocument('1.0','utf-8');

$xml -> load('./dict.xml');

注：若是对html文件进行快速解析，同样的道理

此处使用 loadhtmlfile (‘dict.html’);

（2）创建xpath解析工具

$xpath = new DOMXPATH($xml);

（3）编写xpath查询语句

$sql = '/dict/word[name="'.$word.'"]/name';

注：若是对html文件进行快速解析

$sql = ‘/html/body/div/h2’; //得到body下的div下面的h2标签下的内容

（4）查询语句，返回结果

$words = $xpath->query($sql);

下面是查询语句表的一些语法

二、xml做小型数据库实现六级单词快速查询实例

初步版本：缺点：查询速度慢

//接收单词并解析XML查询相应的单词

$word = isset($_GET['word'])?trim($_GET['word']):'';

if(empty($word)){

exit("I am sorry,I can't catch the word!");

}else{

$xml = new DOMDocument('1.0','utf-8');

$xml -> load('./dict.xml');

// * DOM实现解析并查询

$namelist = $xml->getElementsByTagName('name');

$value = array();

$isfind = false;

foreach($namelist as $v){

if(($v->nodeValue) == $word){

//print_r($v);

echo $word,"<br/>";

echo "Meaning：",$v->nextSibling->nodeValue,"<br/>";

echo "Example：",$v->nextSibling->nextSibling->nodeValue,"<br/>";

//$value['Word'] = $word;

//$value['Meaning'] = $v->nextSibling->nodeValue;

//$value['Example'] = str_replace('/r/n',"<br/>",$v->nextSibling->nextSibling->nodeValue);

$isfind = true;

break;

}

if(!$isfind)

echo "<br/><h3>Sorry,the word is not in the directory</h3>";

使用XPATH改进版本：速度快

使用实例：

$word = isset($_GET['word'])?trim($_GET['word']):'';

if(empty($word)){

exit("I am sorry,I can't catch the word!");

}else{

$xml = new DOMDocument('1.0','utf-8');

$xml -> load('./dict.xml');

$xpath = new DOMXPATH($xml);

//查询dict下面的word，并且name=$word的节点下的//name节点

$sql = '/dict/word[name="'.$word.'"]/name';

$words = $xpath->query($sql);

if($words->length == 0){ //如果没有这个单词

echo "<br/><h3>Sorry,the word is not in the directory</h3>";

exit;

}

//走到这一步，说明查到了

Echo "<b>Word:</b>","       ","<B>$word

</B>","<br/>";

echo "<b>Meaning：</b>",$name->nextSibling->nodeValue,"<br/>";

echo "<b>Example：</b>",$name->nextSibling->nextSibling->nodeValue,"<br/>";

//$value['Word'] = $word;

//$value['Meaning'] = $name->nextSibling->nodeValue;

//$value['Example'] = str_replace('/r/n',"<br/>",$name->nextSibling->nextSibling->nodeValue);

}

附上HTML文件代码：

<html>

<head>

</head>

<style>

//style="text-align:center;"}

</style>

<body>

<div >

<h2>XML做小型数据库实现在线词典</h2>

<form>

</form>

<p>

<?PHP if(isset($value['Word'])) {

foreach($value as $k=>$v){ ?>

<br/>

<?php

}

}?>

</p>

</div>

</body>

</html>

结果如果所示：

三、使用XPATH快速查询html文件实例

$html = new DOMDocument('1.0','utf-8');

$html -> loadhtmlfile('./dict.html');

$xpath= new DOMXPATH($html);

$sql = ‘/html/body/div/h2’; //得到body下的div下面的h2标签下的内容

Echo $xpath->query($sql)->item(0)->nodeValue;

posted on 2015-02-05 11:32 Lover雪儿阅读(657) 评论(0) 编辑收藏举报