PHP DOMDocument：从id获取属性值

Question

I would like to extract the value of the attribute "value" using the id tag. 我想使用id标记提取属性“ value”的值。

My code: 我的代码：

<?php
 $url = 'http://turni.tt-contact.com/Default.aspx';
 $contents = htmlentities(file_get_contents($url));
 echo $contents."\n"; //html
 $dom = new DOMDocument;
 $dom->validateOnParse = true;
 $dom->loadHTML($contents);
 $dom->preserveWhiteSpace = false;
 $data = $dom->getElementById("__VIEWSTATE");
 echo $data->nodeValue;
?>

I would like the attribute "value" -> "THIS": 我想要属性“值”->“此”：

   <input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="THIS">

but the code returns only the html code. 但是该代码仅返回html代码。

What do I need to change? 我需要更改什么？

Also by modifying it to: 也可以通过将其修改为：

$xpath = new DOMXpath($dom);
$data = $xpath->query('//input[@id="__VIEWSTATE"]');
$node = $data->item(0);
echo $node->getAttribute('value');

I get this error: 我收到此错误：

  Fatal error: Call to a member function getAttribute() on null

Answer 1

Try this : 尝试这个：

$data->getAttribute('value');

PHP: DomElement->getAttribute PHP：DomElement-> getAttribute

$attrs = array();
 for ($i = 0; $i < $data->attributes->length; ++$i){
   $node = $data->attributes->item($i);
   $attrs[$node->nodeName] = $node->nodeValue;
 }
 var_dump($attrs);

Answer 2

Don't use htmlentities as it will change the document's HTML tags from : <html> to <html> 不要使用htmlentities因为它会将文档的HTML标记从<html>更改为<html> and your document won't be HTML anymore, just a plain text full of < 并且您的文档将不再是HTML，而只是包含<的纯文本< and > 和> , and so the methods to get nodes won't work. ，因此获取节点的方法将行不通。

PHP DOMDocument：从id获取属性值

问题描述

2 个解决方案

解决方案1
3 已采纳 2017-10-10 14:55:39

解决方案2
0 2017-10-10 19:27:58

PHP DOMDocument：从id获取属性值

问题描述

2 个解决方案

解决方案1 3 已采纳 2017-10-10 14:55:39

解决方案2 0 2017-10-10 19:27:58

解决方案1
3 已采纳 2017-10-10 14:55:39

解决方案2
0 2017-10-10 19:27:58