require_once "simple_html_dom.PHP";
$text = 'foo <div id="t1">Content <div>more stuff</div></div> bar <div>even more</div> baz  <div id="t2">yes</div>';
$html = str_get_html($text);
foreach($html->find('div') as $e) {
    if(isset($e->attr['id']) && preg_match('/^t\d++/',$e->attr['id'])) {
        echo $e->outertext . "\n";
    }
}

输出：

<div id="t1">Content <div>more stuff</div></div>
<div id="t2">yes</div>

在此处下载解析器：http://simplehtmldom.sourceforge.net/

编辑：更多为了我自己的娱乐我试图在正则表达式.这就是我想出的：

$text = 'foo <div id="t1">Content <div>more stuff</div></div> bar <div>even more</div>
      baz <div id="t2">yes <div>aaa<div>bbb<div>ccc</div>bbb</div>aaa</div> </div>';
if(preg_match_all('#<div\s+id="t\d+">[^<>]*(<div[^>]*>(?:[^<>]*|(?1))*</div>)[^<>]*</div>#si',$text,$matches)) {
    print_r($matches[0]);
}

输出：

Array
(
    [0] => <div id="t1">Content <div>more stuff</div></div>
    [1] => <div id="t2">yes <div>aaa<div>bbb<div>ccc</div>bbb</div>aaa</div> </div>
)

还有一个小解释：

<div\s+id="t\d+">  # match an opening 'div' with an id that starts with 't' and some digits
[^<>]*             # match zero or more chars other than '<' and '>'
(                  # open group 1
  <div[^>]*>       #   match an opening 'div'
  (?:              #   open a non-matching group
    [^<>]*         #     match zero or more chars other than '<' and '>'
    |              #     OR
    (?1)           #     recursively match what is defined by group 1
  )*               #   close the non-matching group and repeat it zero or more times
  </div>           #   match a closing 'div'
)                  # close group 1
[^<>]*             # match zero or more chars other than '<' and '>'
</div>             # match a closing 'div'

现在也许你理解为什么人们试图说服你不要使用正则表达式.正如已经指出的那样,如果html格式不正确,它将无济于事：正如我所向你保证的那样,正则表达式会使输出变得比html解析器更大.此外,正则表达式可能会让你的眼睛流血,你的同事(或维护你的软件的人)可能会在看到你做了什么后来找你.