本文实例讲述了PHP经典实用正则表达式。分享给大家供大家参考,具体如下:
对于开发人员来说,正则表达式是一个非常有用的功能,它提供了 查找,匹配,替换 句子,单词,或者其他格式的字符串。这里介绍了几个超实用的php正则表达式,需要的朋友可以参考下。
1. 验证域名检验一个字符串是否是个有效域名
<?php $url = "https://www.baidu.com"; if (preg_match('/^(http|https|ftp)://([A-Z0-9][A-Z0-9_-]*(?:.[A-Z0-9][A-Z0-9_-]*)+):?(d+)?/?/i', $url)) { echo "Your url is ok."; } else { echo "Wrong url."; }
2. 从一个字符串中 突出某个单词
这是一个非常有用的在一个字符串中匹配出某个单词 并且突出它,非常有效的搜索结果
<?php $text = "Sample sentence from KomunitasWeb, regex has become popular in web programming. Now we learn regex. According to wikipedia, Regular expressions (abbreviated as regex or regexp, with plural forms regexes, regexps, or regexen) are written in a formal language that can be interpreted by a regular expression processor"; $text = preg_replace("/(regex)/i", '<span style="background:#5fc9f6">1</span>', $text); echo $text;
function get_the_title(){ return 'Save the search.php file and open style.css. Append the following line to it: '; } $s = 'and php'; $title = get_the_title(); $keys= explode(" ",$s); $title = preg_replace('/('.implode('|', $keys) .')/iu', '<strong>