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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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"
"
gm

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)^(\%.*|Command rejected.*)" Local $sString = "**State Acronym: H - Healthy, W - Warning, C - Critical" & @CRLF & _ "Resource Usage Max Warning Critical State" & @CRLF & _ "----------------------------------------------------------------------------------------------------" & @CRLF & _ "RP0 (ok, active) H" & @CRLF & _ " Control Processor 29.42% 100% 80% 90% H" & @CRLF & _ " DRAM 2840MB(72%) 3938MB 88% 93% H" & @CRLF & _ " bootflash 1889MB(69%) 2753MB 70% 90% H" & @CRLF & _ "ESP0(ok, active) H" & @CRLF & _ " QFP H" & @CRLF & _ " DRAM 81237KB(41%) 196608KB 85% 95% H" & @CRLF & _ " IRAM 207KB(10%) 2048KB 85% 95% H" & @CRLF & _ " CPU Utilization 2.00% 100% 90% 95% H" & @CRLF & _ "" & @CRLF & _ "Load Average" & @CRLF & _ " Slot Status 1-Min 5-Min 15-Min" & @CRLF & _ " RP0 Healthy 1.24 1.20 1.23" & @CRLF & _ "" & @CRLF & _ "Memory (kB)" & @CRLF & _ " Slot Status Total Used (Pct) Free (Pct) Committed (Pct)" & @CRLF & _ " RP0 Healthy 4033104 2909060 (72%) 1124044 (28%) 3749844 (93%)" & @CRLF & _ "" & @CRLF & _ "CPU Utilization" & @CRLF & _ " Slot CPU User System Nice Idle IRQ SIRQ IOwait" & @CRLF & _ " RP0 0 3.51 4.89 0.00 90.10 0.95 0.53 0.00" & @CRLF & _ " 1 2.96 4.55 0.00 90.98 1.06 0.42 0.00" & @CRLF & _ " 2 21.93 2.01 0.00 75.28 0.67 0.09 0.00" & @CRLF & _ " 3 29.17 34.41 0.00 25.93 10.09 0.37 0.00" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ " 2222233333111111111111111111111111111111 111112222222222" & @CRLF & _ " 100" & @CRLF & _ " 90" & @CRLF & _ " 80" & @CRLF & _ " 70" & @CRLF & _ " 60" & @CRLF & _ " 50" & @CRLF & _ " 40" & @CRLF & _ " 30" & @CRLF & _ " 20" & @CRLF & _ " 10" & @CRLF & _ " 0....5....1....1....2....2....3....3....4....4....5....5....6" & @CRLF & _ " 0 5 0 5 0 5 0 5 0 5 0" & @CRLF & _ " CPU% per second (last 60 seconds)" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ " 1 1 1 1 1 1 1" & @CRLF & _ " 439546515464943339403403334255420343303354853430442395424873" & @CRLF & _ " 100" & @CRLF & _ " 90" & @CRLF & _ " 80" & @CRLF & _ " 70" & @CRLF & _ " 60" & @CRLF & _ " 50" & @CRLF & _ " 40" & @CRLF & _ " 30" & @CRLF & _ " 20" & @CRLF & _ " 10 ** **#* * # * * * *** * * * ** * ** *" & @CRLF & _ " 0....5....1....1....2....2....3....3....4....4....5....5....6" & @CRLF & _ " 0 5 0 5 0 5 0 5 0 5 0" & @CRLF & _ " CPU% per minute (last 60 minutes)" & @CRLF & _ " * = maximum CPU% # = average CPU%" & @CRLF & _ "% Ambiguous command" & @CRLF & _ "% Invalid input detected at '^' marker" & @CRLF & _ "% Bad Mask /xx for address X.X.X.X" & @CRLF & _ "% X.X.X.X overlaps with GigabitEthernet0/1" & @CRLF & _ "Command rejected: Conflict between 'nonegotiate' and 'dynamic' status" & @CRLF & _ "% Configuration of multiple subinterfaces of the same main interface with the same VID is not permitted" & @CRLF & _ "% Configuring IP routing on a LAN subinterface is only allowed if that subinterface is already configured as part of a VLAN" & @CRLF & _ "% Inconsistent address and mask" & @CRLF & _ "% Invalid next hop address (it's this router)" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm