PHP中preg_match函数正则匹配的字符串长度问题

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PHP中preg_match函数正则匹配的字符串长度问题_PHP

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May 30, 2016 am 08:47 AM

phppreg_matchfunctionRegular match

项目中，用preg_match正则提取目标内容，死活有问题，代码测得死去活来。

后来怀疑PHP 的preg_match有字符串长度限制，果然，发现“pcre.backtrack_limit ”的值默认只设了100000。

解决办法：ini_set('pcre.backtrack_limit', 999999999);

注：这个参数在php 5.2.0版本之后可用。

另外说说关于：pcre.recursion_limit

pcre.recursion_limit是PCRE的递归限制，这个项如果设很大的值，会消耗所有进程的可用堆栈，最后导致PHP崩溃。

也可以通过修改配置来限制：ini_set('pcre.recursion_limit', 99999);

实际项目应用中，最好也对内存进行限定设置：ini_set('memory_limit', '64M'); , 这样就比较稳妥妥嘎。

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