Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
ig

Test String

Code Generator

Language

Generated Code

use strict; my $str = '"Cache-Control": "max-age=0", "Upgrade-Insecure-Requests": "1", "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36", "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9", "Accept-Encoding": "gzip, deflate", "Accept-Language": "zh-CN,zh;q=0.9,en;q=0.8", "Connection": "close", "Content-Type": "multipart/form-data; boundary=----WebKitFormBoundaryl7d1B1aGsV2wcZwF"} data = "------WebKitFormBoundaryl7d1B1aGsV2wcZwF Content-Disposition: form-data; name=\\"id\\" %{ (#request.map=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) + (#request.map.setBean(#request.get(\'struts.valueStack\')) == true).toString().substring(0,0) + (#request.map2=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) + (#request.map2.setBean(#request.get(\'map\').get(\'context\')) == true).toString().substring(0,0) + (#request.map3=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) + (#request.map3.setBean(#request.get(\'map2\').get(\'memberAccess\')) == true).toString().substring(0,0) + (#request.get(\'map3\').put(\'excludedPackageNames\',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) + (#request.get(\'map3\').put(\'excludedClasses\',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) + (#application.get(\'org.apache.tomcat.InstanceManager\').newInstance(\'freemarker.template.utility.Execute\').exec({\'whoami\'})) } ------WebKitFormBoundaryl7d1B1aGsV2wcZwF\\xe2\\x80\\x94" /?name=%{(#dm=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS).(#_memberAccess?(#_memberAccess=#dm):((#container=#context[\'com.opensymphony.xwork2.ActionContext.container\']).(#ognlUtil=#container.getInstance(@com.opensymphony.xwork2.ognl.OgnlUtil@class)).(#ognlUtil.getExcludedPackageNames().clear()).(#ognlUtil.getExcludedClasses().clear()).(#context.setMemberAccess(#dm)))).(#cmd=\'cat /etc/passwd\').(#iswin=(@java.lang.System@getProperty(\'os.name\').toLowerCase().contains(\'win\'))).(#cmds=(#iswin?{\'cmd.exe\',\'/c\',#cmd}:{\'/bin/bash\',\'-c\',#cmd})).(#p=new java.lang.ProcessBuilder(#cmds)).(#p.redirectErrorStream(true)).(#process=#p.start()).(@org.apache.commons.io.IOUtils@toString(#process.getInputStream()))} /index.action?method:#_memberAccess=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS,#res=@org.apache.struts2.ServletActionContext@getResponse(),#res.setCharacterEncoding(#parameters.encoding[0]),#w=#res.getWriter(),#s=new java.util.Scanner(@java.lang.Runtime@getRuntime().exec(#parameters.cmd[0]).getInputStream()).useDelimiter(#parameters.pp[0]),#str=#s.hasNext()?#s.next():#parameters.ppp[0],#w.print(#str),#w.close(),1?#xx:#request.toString&pp=\\\\A&ppp= &encoding=UTF-8&cmd=cat /etc/passwd ------WebKitFormBoundaryl7d1B1aGsV2wcZwF\\r\\nContent-Disposition: form-data; name=\\"id\\"\\r\\n\\r\\n%{\\r\\n(#request.map=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\\r\\n(#request.map.setBean(#request.get(\'struts.valueStack\')) == true).toString().substring(0,0) +\\r\\n(#request.map2=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\\r\\n(#request.map2.setBean(#request.get(\'map\').get(\'context\')) == true).toString().substring(0,0) +\\r\\n(#request.map3=#@org.apache.commons.collections.BeanMap@{}).toString().substring(0,0) +\\r\\n(#request.map3.setBean(#request.get(\'map2\').get(\'memberAccess\')) == true).toString().substring(0,0) +\\r\\n(#request.get(\'map3\').put(\'excludedPackageNames\',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) +\\r\\n(#request.get(\'map3\').put(\'excludedClasses\',#@org.apache.commons.collections.BeanMap@{}.keySet()) == true).toString().substring(0,0) +\\r\\n(#application.get(\'org.apache.tomcat.InstanceManager\').newInstance(\'freemarker.template.utility.Execute\').exec({\'CMD\'}))\\r\\n}\\r\\n------WebKitFormBoundaryl7d1B1aGsV2wcZwF--\\xe2\\x80\\x94 '; my $regex = qr/\%[\s|\\r|\\n]*\{[\s|\\r|\\n]*(?:[\s|\\r|\\n]*\(\#[^\=]+\=[^\)]+\)\.)/ip; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html