如何使用正则表达式从 HTML 获取数据

How to get data from HTML using regex

我关注HTML

<table class="profile-stats">
  <tr>
    <td class="stat">
      <div class="statnum">8</div>
      <div class="statlabel"> Tweets </div>
    </td>
    <td class="stat">
        <a href="/THEDJMHA/following">
          <div class="statnum">13</div>
          <div class="statlabel"> Following </div>
        </a>
    </td>
    <td class="stat stat-last">
        <a href="/THEDJMHA/followers">
          <div class="statnum">22</div>
          <div class="statlabel"> Followers </div>
        </a>
    </td>
  </tr>
</table>

我想从 <td class="stat stat-last"> => <div class="statnum"> = 22.

中获取值

我尝试了以下正则表达式,但没有找到任何匹配项。

/<div\sclass="statnum">^(.)\?<\/div>/ig

我认为如果您为此使用 XML 解析器而不是正则表达式会更好。简单XML 可以为您完成这项工作:http://php.net/manual/en/book.simplexml.php

您可以这样编辑您的图案:

/<div\sclass="statnum">(.*?)<\/div>/ig
/<td class="stat stat-last">.*?<div class="statnum">(\d+)/si

您的匹配项在第一个捕获组中。注意最后使用了 s 选项。使'。'匹配换行符。

这是使用解析器完成此操作的方法。

<?php
$html = '<table class="profile-stats">
  <tr>
    <td class="stat">
      <div class="statnum">8</div>
      <div class="statlabel"> Tweets </div>
    </td>
    <td class="stat">
        <a href="/THEDJMHA/following">
          <div class="statnum">13</div>
          <div class="statlabel"> Following </div>
        </a>
    </td>
    <td class="stat stat-last">
        <a href="/THEDJMHA/followers">
          <div class="statnum">22</div>
          <div class="statlabel"> Followers </div>
        </a>
    </td>
  </tr>
</table>';
$doc = new DOMDocument(); //make a dom object
$doc->loadHTML($html);
$tds = $doc->getElementsByTagName('td');
foreach ($tds as $cell) { //loop through all Cells
    if(strpos($cell->getAttribute('class'), 'stat-last')){
        $divs = $cell->getElementsByTagName('div');
        foreach($divs as $div) { // loop through all divs of the cell
            if($div->getAttribute('class') == 'statnum'){
                echo $div->nodeValue;
            }
        }
    }
}

输出:

22

...或使用 xpath...

$doc = new DOMDocument(); //make a dom object
$doc->loadHTML($html);
$xpath = new DOMXpath($doc);
$statnums = $xpath->query("//td[@class='stat stat-last']/a/div[@class='statnum']");
foreach($statnums as $statnum) {
    echo $statnum->nodeValue;
}

输出:

22

或者如果您真的想对其进行正则表达式...

<?php
$html = '<table class="profile-stats">
  <tr>
    <td class="stat">
      <div class="statnum">8</div>
      <div class="statlabel"> Tweets </div>
    </td>
    <td class="stat">
        <a href="/THEDJMHA/following">
          <div class="statnum">13</div>
          <div class="statlabel"> Following </div>
        </a>
    </td>
    <td class="stat stat-last">
        <a href="/THEDJMHA/followers">
          <div class="statnum">22</div>
          <div class="statlabel"> Followers </div>
        </a>
    </td>
  </tr>
</table>';
preg_match('~td class=".*?stat-last">.*?<div class="statnum">(.*?)<~s', $html, $num);
echo $num[1];

输出:

22

正则表达式演示:https://regex101.com/r/kM6kI2/1