从HTML获取domXPath的值

Question

我需要从html中解析<span id="the_name">标记的内容 html看起来像这样：

...
<span id="userName" class="username"></span> 
<div class="main"> 
 <div class="menu"> 
  <div id="totals" class="totals" >
  </div> 
  <ul id="alter_menu"> 
  </ul> 
  <div class="content"> 
   <br /> 
   <table width="70%" style="margin-left: auto; margin-right: auto;"> 
   <tr> 
    <td class="major_text" align="center">
    <br/> 
    <span id="verbatim" class="sender"> Alexander</span>
    </td> 
   </tr> 
   <tr> 
   <td>
    </td> 
    </tr> 
   <tr> 
   <td class="newline"> 
  </td>
</div>
...

我运行的代码：

$dom = new domDocument($html);
$xpath = new domXPath($dom);
$nodes = $xpath->query('//span[@id="verbatim"]');
echo $nodes->item(0)->nodeValue;

问题是我一直为$nodes->item(0)->nodeValue获得 NULL ，我不知道如何检查这个domElement。

当然，我需要Alexander值

Answer 1

您只需实例化DOMDocument，然后使用->loadHTML()实际加载HTML标记：

$dom = new domDocument();
libxml_use_internal_errors(true);
$dom->loadHTML($html); // this line is important
$xpath = new domXPath($dom);
$nodes = $xpath->query('//span[@id="verbatim"]');
echo $nodes->item(0)->nodeValue;

Sample Output

->evaluate()也可以使用：

echo $xpath->evaluate('string(//span[@id="verbatim"])');