新人求教~关于正则的模式修正符e的有关问题，为啥小弟我感觉没啥用呢 -PHP Tutorial-php.cn

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新人求教~关于正则的模式修正符e的有关问题，为啥小弟我感觉没啥用呢

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Jun 13, 2016 pm 12:45 PM

comnbspphpreplace

新人求教~关于正则的模式修正符e的问题，为啥我感觉没啥用呢？
比如这两段代码，匹配字符串中的网址链接

这是使用模式修正符e的：

$urlPattern = "/(www.|https?:\/\/|ftp:\/\/|news:\/\/|telnet:\/\/){1}([^\[\"']+?)(com|net|org)(\/[\w-\.\/\?\%\&\=]*)?/ei";

$url="PHP的地址是：www.php.com";

echo preg_replace($urlPattern, "'\\2'.'\\3'", $url);

这是未使用模式修正符e的：

$urlPattern = "/(www.|https?:\/\/|ftp:\/\/|news:\/\/|telnet:\/\/){1}([^\[\"']+?)(com|net|org)(\/[\w-\.\/\?\%\&\=]*)?/i";

$url="PHP的地址是：www.php.com";

echo preg_replace($urlPattern, '\\2'.'\\3', $url);

输出结果是一样的啊~
都是将www.php.com替换为php.com

我觉得也就是多了层双引号而已呢、、、
反而不用e还感觉更简单一点呢

这个e到底是怎么回事？

正则 PHP

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