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

/
/

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r".*ad.srccountry=(?<cs1>.*?)\s.*$" test_str = "0|Fortinet|FortiGate-600E|3.2.1,build1204 (DA)|1239233|app-ctrl utm pass|4|start=Mar 06 2022 23:10:08 logver=232123123 deviceExternalId=FGBHAAAAAA1 dvchost=production01 ad.vd=prod01 ad.eventtime=1646604609212138288 ad.tz=+0100 ad.logid=0000000013 cat=traffic ad.subtype=forward deviceSeverity=notice src=10.0.0.2 spt=37628 deviceInboundInterface=Dev LAN ad.srcintfrole=lan dst=70.70.70.2 dpt=443 deviceOutboundInterface=VL-Develop1 ad.dstintfrole=undefined ad.srccountry=Norway ad.dstcountry=Denmark externalID=10999383 proto=6 act=close ad.policyid=67 ad.policytype=policy ad.poluuid=dca6b9de-adc11-51e2-d100-3cc871c8edae ad.policyname=prod01 to Internet app=HTTPS ad.trandisp=noop ad.duration=1 out=1446 in=4377 ad.sentpkt=11 ad.rcvdpkt=12 ad.shapingpolicyid=1 ad.shapersentname=Production-01 ad.shaperdropsentbyte=0 ad.shaperrcvdname=Filter-WAN ad.shaperdroprcvdbyte=0 ad.appcat=unscanned ad.mastersrcmac=a1:a1:a1:a1:a1:a1 ad.srcmac=a1:a1:a1:a1:a1:a1 ad.srcserver=0 tz=\"+0100\"" matches = re.search(regex, test_str) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html