请教正则必须包含如何匹配呢

正则：

(.*)

内容：

str

标题一

标题二

目标：(必须包含

)

标题二

当前错误结果：(匹配成了整段了)
标题一

标题二

回复讨论(解决方案)

加上 U，禁止贪婪

是这个意思吗

$str = '<li>str</li><li><a href="/x.html">标题一</a></li><a href="/BAMC"><div class="plst"><b>标题二</b></div></a>';preg_match_all("/<a.*?><div class=\"plst\"><b>(.*)<\/b><\/div><\/a>/is",$str,$match);echo "<pre class="brush:php;toolbar:false">";print_r($match);

是这个意思吗

$str = '<li>str</li><li><a href="/x.html">标题一</a></li><a href="/BAMC"><div class="plst"><b>标题二</b></div></a>';preg_match_all("/<a.*?><div class=\"plst\"><b>(.*)<\/b><\/div><\/a>/is",$str,$match);echo "<pre class="brush:php;toolbar:false">";print_r($match);

正确结果：
<a href="/BAMC"><div class="plst"><b>标题二</b></div></a>

当前错误结果：
标题一<a href="/BAMC"><div class="plst"><b>标题二</b></div></a>

我试了你这个，还是匹配了下面这种结果。

preg_match_all("/<a.*?><div class=\"plst\"><b>(.*)<\/b><\/div><\/a>/isU",$str,$match);//加上U，禁止贪婪模式

preg_match_all("/<a.*?><div class=\"plst\"><b>(.*)<\/b><\/div><\/a>/isU",$str,$match);//加上U，禁止贪婪模式

该死的csdn
preg_match_all("/

(.*)<\/b><\/div><\/a>/is U",$str,$match);

加上 U，禁止贪婪
好象不是贪婪的问题，因为他在匹配到结果就立即结束了。

加了U

$str = '<li>str</li><li><a href="/x.html">标题一</a></li><a href="/BAMC"><div class="plst"><b>标题二</b></div></a>';preg_match_all("/<a.*?><div class=\"plst\"><b>(.*)<\/b><\/div><\/a>/U",$str,$match);echo "<pre class="brush:php;toolbar:false">";print_r($match);

结果：

<pre class="brush:php;toolbar:false">Array(    [0] => Array        (            [0] => <a href="/x.html">标题一</a></li><a href="/BAMC"><div class="plst"><b>标题二</b></div></a>        )    [1] => Array        (            [0] => 标题二        ))

preg_match_all("/<a.*?><div class=\"plst\"><b>(.*)<\/b><\/div><\/a>/isU",$str,$match);//加上U，禁止贪婪模式

该死的csdn
preg_match_all("/

(.*)<\/b><\/div><\/a>/is U",$str,$match);



结果：

Array(    [0] => Array        (            [0] => <a href="/x.html">标题一</a></li><a href="/BAMC"><div class="plst"><b>标题二</b></div></a>        )    [1] => Array        (            [0] => 标题二        ))

前面一堆这个还是多余存在的：
标题一

给个提醒
匹配一些有边界的内容，应以 边界+ 排除边界+ 边界 这样的形式写正则，避免随意地用圆点
尤其是html等标记语言，因为标记语言的特性就是标记，中间含有换行也是合法的，圆点不能涵盖，随便用圆点就有点想当然认为源字串一定工整了
举个极端例子如：
href="
abc/abc.html">
ABC

这段html字串完全合法，一点都不影响网页的显示，但正则就要想好了

"[^"]*"
<[^>]+>
[^<]*

$s =<<< TXT<li>str</li><li><a href="/x.html">标题一</a></li><a href="/BAMC"><div class="plst"><b>标题二</b></div></a>TXT;preg_match('/.+(<a.+?<div class="plst".+?a>)/is', $s, $m);echo $m[1];

<a href="/BAMC"><div class="plst"><b>标题二</b></div></a>

再简化一下

preg_match('/.+()/is', $s, $m);echo $m[1];/*<a href="/BAMC"><div class="plst"><b>标题二</b></div></a>*/

Related labels：

请教正则必须包含如何匹配呢

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