黑科技！一键提取QQ名片工具！

function getCodeLangExt($str) {
    // 兼容 双引号/单引号/无引号 的lang值
    $pattern = '/[code(?:s+lang=(?:"([^"]+)"|'([^']+)'|([^s]]+)))?]/i';
    preg_match($pattern, $str, $matches);
    
    // 优先取双引号匹配，再单引号，最后无引号
    $lang = $matches[1] ?? $matches[2] ?? $matches[3] ?? null;
    return $lang;
}

<form action="/my-handling-form-page" method="post">
  <ul>
    <li>
      <label for="name">Name:</label>
      <input type="text" id="name" name="user_name" />
    </li>
    <li>
      <label for="mail">E-mail:</label>
      <input type="email" id="mail" name="user_email" />
    </li>
    <li>
      <label for="msg">Message:</label>
      <textarea id="msg" name="user_message"></textarea>
    </li>
  </ul>
</form>