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"(?<date>\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}.\d{3}Z)\s+(?<src>\w+)\s+CEF:(?<version>\d+)\|(?<device_vendor>\w+)\|(?<device_product>\w+)\|(?<device_version>[\d.]*)\|(?<signature_id>[\w\d]*)" test_str = "2018-12-13T10:25:52.647Z imdgnparser01 CEF:0|MCAS|SIEM_Agent|0.138.173|EVENT_CATEGORY_AZURE_OPERATION|Azure operation|0|externalId=ffc53f2d8811bde87ee94bb86dc062442ec48df5303dd262e424ceeeecba8f91 rt=1544696752647 start=1544696752647 end=1544696752647 msg=ListAccountSas StorageAccounts: resource phastneprd02 - Started suser=11c174dc-1945-4a9a-a36b-c79a0f246b9b destinationServiceName=Microsoft Azure dvc=13.94.250.141 requestClientApplication= cs1Label=portalURL cs1=https://starsweb.eu2.portal.cloudappsecurity.com/#/audits?activity.id\\=eq(ffc53f2d8811bde87ee94bb86dc062442ec48df5303dd262e424ceeeecba8f91,) cs2Label=uniqueServiceAppIds cs2=APPID_AZURE cs3Label=targetObjects cs3=phastneprd02,Microsoft.Storage/storageAccounts,DWH_DataPlatform,,Operation status,Windows Azure Application Insights cs4Label=policyIDs cs4= c6a1Label=\"Device IPv6 Address\" c6a1=#015" 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