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15个实用的PHP正则表达式_PHP教程

时间：2021-07-01 10:21:17 帮助过：5人阅读

15 个实用的 PHP 正则表达式


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。这篇文章主要介绍了15个超实用的php正则表达式，需要的朋友可以参考下。在这篇文章里，我已经编写了15个超有用 的正则表达式，WEB开发人员都应该将它收藏到自己的工具包。

验证域名检验一个字符串是否是个有效域名

  1. $url = https://www.gxlcms.com/"http://komunitasweb.com/"https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  2. ifhttps://www.gxlcms.com/ (preg_match(https://www.gxlcms.com/'/^(http|https|ftp)://([A-Z0-9][A-Z0-9_-]*(?:.[A-Z0-9][A-Z0-9_-]*)+):?(d+)?/?/i'https://www.gxlcms.com/, $url)) { https://www.gxlcms.com/https://www.gxlcms.com/
  3.   echo "Your url is ok."https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  4. } elsehttps://www.gxlcms.com/ { https://www.gxlcms.com/https://www.gxlcms.com/
  5.   echo "Wrong url."https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  6. } https://www.gxlcms.com/

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

  1. $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  https://www.gxlcms.com/https://www.gxlcms.com/
  2.  https://www.gxlcms.com/
  3. regexp, with plural forms regexes, regexps, or regexen) are written in a formal language that can be interpreted by a regular expression processor";  https://www.gxlcms.com/
  4. $text = preg_replace("/b(regex)b/i"https://www.gxlcms.com/, https://www.gxlcms.com/'1https://www.gxlcms.com/'https://www.gxlcms.com/, $text);  https://www.gxlcms.com/https://www.gxlcms.com/
  5. echo $text; https://www.gxlcms.com/

突出查询结果在你的 WordPress 博客里就像刚才我说的，上面的那段代码可以很方便的搜索出结果，而这里是一个更好的方式去执行搜索在某个WordPress的博客上打开你的文件 search.php ，然后找到 方法 the_title() 然后用下面代码替换掉它

  1. echo $title;  https://www.gxlcms.com/https://www.gxlcms.com/
  2.  https://www.gxlcms.com/
  3. Now, just before the modified line, add thishttps://www.gxlcms.com/ code:  https://www.gxlcms.com/https://www.gxlcms.com/
  4.  https://www.gxlcms.com/
  6.   $title   = get_the_title();  https://www.gxlcms.com/
  7.   $keys= explode(" "https://www.gxlcms.com/,$s);  https://www.gxlcms.com/https://www.gxlcms.com/
  8.   $title   = preg_replace('/('https://www.gxlcms.com/.implode(https://www.gxlcms.com/'|'https://www.gxlcms.com/, $keys) .https://www.gxlcms.com/')/iu'https://www.gxlcms.com/,  https://www.gxlcms.com/https://www.gxlcms.com/
  9.     '\0'https://www.gxlcms.com/,  https://www.gxlcms.com/https://www.gxlcms.com/
  10.     $title);  https://www.gxlcms.com/
  11. >  https://www.gxlcms.com/
  12.  https://www.gxlcms.com/
  13. Save the search.php file and open style.css. Append the following line to it:  https://www.gxlcms.com/
  14.  https://www.gxlcms.com/
  15. strong.search-excerpt { background: yellow; } 
    https://www.gxlcms.com/

从HTML文档中获得全部图片

如果你曾经希望去获得某个网页上的全部图片，这段代码就是你需要的，你可以轻松的建立一个图片下载机器人

  1. $images = array(); https://www.gxlcms.com/https://www.gxlcms.com/
  2. preg_match_all('/(img|src)=("|'https://www.gxlcms.com/)[^"https://www.gxlcms.com/'>]+/i'https://www.gxlcms.com/, $data, $media); https://www.gxlcms.com/https://www.gxlcms.com/
  3. unset($data); https://www.gxlcms.com/
  4. $data=preg_replace('/(img|src)("|'https://www.gxlcms.com/|="|=https://www.gxlcms.com/')(.*)/i'https://www.gxlcms.com/,https://www.gxlcms.com/"$3"https://www.gxlcms.com/,$media[https://www.gxlcms.com/0https://www.gxlcms.com/]); https://www.gxlcms.com/https://www.gxlcms.com/
  5. foreach($data as $url) https://www.gxlcms.com/
  6. { https://www.gxlcms.com/
  7.   $info = pathinfo($url); https://www.gxlcms.com/
  8.   ifhttps://www.gxlcms.com/ (isset($info[https://www.gxlcms.com/'extension'https://www.gxlcms.com/])) https://www.gxlcms.com/https://www.gxlcms.com/
  9.   { https://www.gxlcms.com/
  10.     ifhttps://www.gxlcms.com/ (($info[https://www.gxlcms.com/'extension'https://www.gxlcms.com/] == https://www.gxlcms.com/'jpg'https://www.gxlcms.com/) || https://www.gxlcms.com/https://www.gxlcms.com/
  11.     ($info['extension'https://www.gxlcms.com/] == https://www.gxlcms.com/'jpeg'https://www.gxlcms.com/) || https://www.gxlcms.com/https://www.gxlcms.com/
  12.     ($info['extension'https://www.gxlcms.com/] == https://www.gxlcms.com/'gif'https://www.gxlcms.com/) || https://www.gxlcms.com/https://www.gxlcms.com/
  13.     ($info['extension'https://www.gxlcms.com/] == https://www.gxlcms.com/'png'https://www.gxlcms.com/)) https://www.gxlcms.com/https://www.gxlcms.com/
  14.     array_push($images, $url); https://www.gxlcms.com/
  15.   } https://www.gxlcms.com/
  16. } https://www.gxlcms.com/

删除重复字母

经常重复输入字母? 这个表达式正适合.

  1. $text = preg_replace(https://www.gxlcms.com/"/s(w+s)1/i"https://www.gxlcms.com/, https://www.gxlcms.com/"$1"https://www.gxlcms.com/, $text); https://www.gxlcms.com/https://www.gxlcms.com/

删除重复的标点

功能同上，但只是面对标点，白白重复的逗号

  1. $text = preg_replace(https://www.gxlcms.com/"/.+/i"https://www.gxlcms.com/, https://www.gxlcms.com/"."https://www.gxlcms.com/, $text); https://www.gxlcms.com/https://www.gxlcms.com/

匹配一个XML或者HTML标签

这个简单的函数有两个参数：第一个是你要匹配的标签，第二个是包含XML或HTML的变量，再强调下，这个真的很强大

  1. function get_tag( $tag, $xml ) { https://www.gxlcms.com/https://www.gxlcms.com/
  2. $tag = preg_quote($tag); https://www.gxlcms.com/
  3. preg_match_all('{<'https://www.gxlcms.com/.$tag.https://www.gxlcms.com/'[^>]*>(.*?).$tag.https://www.gxlcms.com/'>.'https://www.gxlcms.com/}', https://www.gxlcms.com/https://www.gxlcms.com/
  4.           $xml, https://www.gxlcms.com/
  5.           $matches, https://www.gxlcms.com/
  6.           PREG_PATTERN_ORDER); https://www.gxlcms.com/
  7.  https://www.gxlcms.com/
  8. returnhttps://www.gxlcms.com/ $matches[https://www.gxlcms.com/1https://www.gxlcms.com/]; https://www.gxlcms.com/https://www.gxlcms.com/
  9. } https://www.gxlcms.com/

匹配具有属性值的XML或者HTML标签

这个功能和上面的非常相似，但是它允许你匹配的标签内部有属性值，例如你可以轻松匹配 

  1. function get_tag( $attr, $value, $xml, $tag=https://www.gxlcms.com/nullhttps://www.gxlcms.com/ ) { https://www.gxlcms.com/https://www.gxlcms.com/
  2. ifhttps://www.gxlcms.com/( is_null($tag) ) https://www.gxlcms.com/https://www.gxlcms.com/
  3.   $tag = '\w+'https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  4. elsehttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  5.   $tag = preg_quote($tag); https://www.gxlcms.com/
  6.  https://www.gxlcms.com/
  7. $attr = preg_quote($attr); https://www.gxlcms.com/
  8. $value = preg_quote($value); https://www.gxlcms.com/
  9.  https://www.gxlcms.com/
  10. $tag_regex = "/<("https://www.gxlcms.com/.$tag.https://www.gxlcms.com/")[^>]*$attr\s*=\s*"https://www.gxlcms.com/. https://www.gxlcms.com/https://www.gxlcms.com/
  11.         "(['\"])$value\\2[^>]*>(.*?)<\/\\1>/"https://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  12.  https://www.gxlcms.com/
  13. preg_match_all($tag_regex, https://www.gxlcms.com/
  14.          $xml, https://www.gxlcms.com/
  15.          $matches, https://www.gxlcms.com/
  16.          PREG_PATTERN_ORDER); https://www.gxlcms.com/
  17.  https://www.gxlcms.com/
  18. returnhttps://www.gxlcms.com/ $matches[https://www.gxlcms.com/3https://www.gxlcms.com/]; https://www.gxlcms.com/https://www.gxlcms.com/
  19. } https://www.gxlcms.com/

匹配十六进制颜色值

web开发者的另一个有趣的工具，它允许你匹配和验证十六进制颜色值.

  1. $string = https://www.gxlcms.com/"#555555"https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  2. ifhttps://www.gxlcms.com/ (preg_match(https://www.gxlcms.com/'/^#(?:(?:[a-fd]{3}){1,2})$/i'https://www.gxlcms.com/, $string)) { https://www.gxlcms.com/https://www.gxlcms.com/
  3. echo "example 6 successful."https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  4. } https://www.gxlcms.com/

查找页面 title

这段代码方便查找和打印 网页 和 之间的内容

  1. $fp = fopen(https://www.gxlcms.com/"http://www.catswhocode.com/blog"https://www.gxlcms.com/,https://www.gxlcms.com/"r"https://www.gxlcms.com/); https://www.gxlcms.com/https://www.gxlcms.com/
  2. whilehttps://www.gxlcms.com/ (!feof($fp) ){ https://www.gxlcms.com/https://www.gxlcms.com/
  3.   $page .= fgets($fp, 4096https://www.gxlcms.com/); https://www.gxlcms.com/https://www.gxlcms.com/
  4. } https://www.gxlcms.com/
  5.  https://www.gxlcms.com/
  6. $titre = eregi("(.*)"https://www.gxlcms.com/,$page,$regs); https://www.gxlcms.com/https://www.gxlcms.com/
  7. echo $regs[1https://www.gxlcms.com/]; https://www.gxlcms.com/https://www.gxlcms.com/
  8. fclose($fp); https://www.gxlcms.com/

解释 Apache 日志

大多数网站使用的都是著名的Apache服务器，如果你的网站也是，那么使用PHP正则表达式解析 apache 服务器日志 怎么样？

  1. //Logs: Apache web serverhttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  2. //Successful hits to HTML files only. Useful for counting the number of page views.https://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  3. '^((?#client IP or domain name)S+)s+((?#basic authentication)S+s+S+)s+[((?#date and time)[^]]+)]s+"(?:GET|POST|HEAD) ((?#file)/[^ ?"]+?.html?)??((?#parameters)[^ ?"]+)? HTTP/[0-9.]+"s+(?#status code)200s+((?#bytes transferred)[-0-9]+)s+"((?#referrer)[^"]*)"s+"((?#user agent)[^"]*)"$'https://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  4.  https://www.gxlcms.com/
  5. //Logs: Apache web serverhttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  6. //404 errors onlyhttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  7. '^((?#client IP or domain name)S+)s+((?#basic authentication)S+s+S+)s+[((?#date and time)[^]]+)]s+"(?:GET|POST|HEAD) ((?#file)[^ ?"]+)??((?#parameters)[^ ?"]+)? HTTP/[0-9.]+"s+(?#status code)404s+((?#bytes transferred)[-0-9]+)s+"((?#referrer)[^"]*)"s+"((?#user agent)[^"]*)"$'https://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/

使用智能引号代替双引号

如果你是一个印刷爱好者，你将喜欢这个允许用智能引号代替双引号的正则表达式，这个正则被WORDPRESS在其内容上使用

  1. preg_replace(https://www.gxlcms.com/'B"b([^"x84x93x94rn]+)b"B'https://www.gxlcms.com/, https://www.gxlcms.com/'?1?'https://www.gxlcms.com/, $text); https://www.gxlcms.com/https://www.gxlcms.com/

检验密码的复杂度

这个正则表达式将检测输入的内容是否包含6个或更多字母，数字，下划线和连字符. 输入必须包含至少一个大写字母，一个小写字母和一个数字

'A(?=[-_a-zA-Z0-9]*?[A-Z])(?=[-_a-zA-Z0-9]*?[a-z])(?=[-_a-zA-Z0-9]*?[0-9])[-_a-zA-Z0-9]{6,}z'

WordPress: 使用正则获得帖子上的图片

我知道很多人是WORDPRESS的使用者，你可能会喜欢并且愿意使用 那些从帖子的内容检索下来的图像代码。使用这个代码在你的BLOG只需要复制下面代码到你的某个文件里

  1. ifhttps://www.gxlcms.com/ (have_posts()) : ?> https://www.gxlcms.com/https://www.gxlcms.com/
  2. whilehttps://www.gxlcms.com/ (have_posts()) : the_post(); ?> https://www.gxlcms.com/https://www.gxlcms.com/
  3.  https://www.gxlcms.com/
  5. $szPostContent = $post->post_content; https://www.gxlcms.com/
  6. $szSearchPattern = '~]* />~'https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  7.  https://www.gxlcms.com/
  8. // Run preg_match_all to grab all the images and save the results in $aPicshttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  9. preg_match_all( $szSearchPattern, $szPostContent, $aPics ); https://www.gxlcms.com/
  10.  https://www.gxlcms.com/
  11. // Check to see if we have at least 1 imagehttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  12. $iNumberOfPics = count($aPics[0https://www.gxlcms.com/]); https://www.gxlcms.com/https://www.gxlcms.com/
  13.  https://www.gxlcms.com/
  14. ifhttps://www.gxlcms.com/ ( $iNumberOfPics > https://www.gxlcms.com/0https://www.gxlcms.com/ ) { https://www.gxlcms.com/https://www.gxlcms.com/
  15.    // Now here you would do whatever you need to do with the imageshttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  16.    // For this example the images are just displayedhttps://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  17.    forhttps://www.gxlcms.com/ ( $i=https://www.gxlcms.com/0https://www.gxlcms.com/; $i < $iNumberOfPics ; $i++ ) { https://www.gxlcms.com/https://www.gxlcms.com/
  18.      echo $aPics[0https://www.gxlcms.com/][$i]; https://www.gxlcms.com/https://www.gxlcms.com/
  19.    }; https://www.gxlcms.com/
  20. }; https://www.gxlcms.com/
  21.  https://www.gxlcms.com/
  22. endwhile; https://www.gxlcms.com/
  23. endif; https://www.gxlcms.com/
  24. > https://www.gxlcms.com/

自动生成笑脸图案

被WordPress使用的另一个方法, 这段代码可使你把图像自动更换一个笑脸符号

  1. $texte=https://www.gxlcms.com/'A text with a smiley 'https://www.gxlcms.com/; https://www.gxlcms.com/https://www.gxlcms.com/
  2. echo str_replace(':-)'https://www.gxlcms.com/,https://www.gxlcms.com/''https://www.gxlcms.com/,$texte); https://www.gxlcms.com/https://www.gxlcms.com/

移除图片的链接

  1. "Content-Type"https://www.gxlcms.com/ content=https://www.gxlcms.com/"text/html; charset=utf-8"https://www.gxlcms.com/ /> https://www.gxlcms.com/https://www.gxlcms.com/
  3.   $str = ' https://www.gxlcms.com/
  4.     "http://www.jobbole.com/"https://www.gxlcms.com/>jobbole其他字符 https://www.gxlcms.com/https://www.gxlcms.com/
  5.     "http://www.sohu.com/"https://www.gxlcms.com/>sohu https://www.gxlcms.com/https://www.gxlcms.com/
  6.     "http://www.sohu.com/"https://www.gxlcms.com/>"http://www.fashion-press.net/img/news/3176/mot_06.jpg"https://www.gxlcms.com/ /> https://www.gxlcms.com/https://www.gxlcms.com/
  7.     
    '; https://www.gxlcms.com/
  8.  https://www.gxlcms.com/
  9.   //echo preg_replace("/()()(<\/a>)/", '$2', $str); https://www.gxlcms.com/ https://www.gxlcms.com/https://www.gxlcms.com/
  10.   echo preg_replace("/()()(<\/a>)/"https://www.gxlcms.com/, https://www.gxlcms.com/'\2'https://www.gxlcms.com/, $str);  https://www.gxlcms.com/https://www.gxlcms.com/
  11. > https://www.gxlcms.com/

以上就是15个超实用的php正则表达式，希望对大家的学习有所帮助。

www.bkjia.comhttps://www.gxlcms.com/truehttps://www.gxlcms.com/http://www.bkjia.com/PHPjc/1078009.htmlhttps://www.gxlcms.com/TechArticlehttps://www.gxlcms.com/15 个实用的 PHP 正则表达式 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...https://www.gxlcms.com/

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