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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'LogName=LoginPI Events EventCode=1300 EventType=4 ComputerName=RNBSVSIMGT02.rightnetworks.com SourceName=Login Threshold Exceeded Type=Information RecordNumber=285782 Keywords=Classic TaskCategory=None OpCode=Info Message={ "Description": "Total login time (48s) exceeded threshold of 45s (6.67%)", "Actual value": "48", "Threshold value": "45", "AccountId": "4c06e54e-ab5f-47a6-2cc7-08d807c9fae2", "AccountName": "rightnetworks\\\\eloginpi049", "LauncherName": "RNBSVSI21", "Locale": "English (United States)", "RemotingProtocol": "Rdp", "Resolution": "1920 × 1080", "ScaleFactor": "100%", "TargetHost": "BPSQCP00S143", "TargetOS": "Microsoft Windows Server 2016 Standard 10.0.14393 (1607)", "EnvironmentName": "BPSQCP00S143", "EnvironmentId": "06a3c4a2-6f73-4c54-94e9-08d8040960f8", "Title": "Login time threshold exceeded"'; my $regex = qr/Actual\s+value\":\s+\"(?<actual_value>[^\"]+)\"/mp; 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