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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"ActiveParticipant.*?\sUserID=\"+?(?<atnaUserID>[^\"]+)\".+?UserIsRequestor=\"true\"", flags=re.DOTALL) test_str = ("1765 <86>1 2020-11-16T09:50:50+01:00 localhost testSyslogXds SOAP_KSW-RI-Z1_100000000000023_000000000000011 IHE+RFC-3881 [origin swVersion=\"4.7.0\" software=\"Orchestra\"] <?xml version=\"1.0\" encoding=\"UTF-8\"?><AuditMessage><EventIdentification EventActionCode=\"C\" EventDateTime=\"2020-11-16T09:50:50.755+01:00\" EventOutcomeIndicator=\"0\"><EventID codeSystemName=\"DCM\" csd-code=\"110110\" originalText=\"Patient Record\"/><EventTypeCode codeSystemName=\"IHE Transactions\" csd-code=\"ITI-44\" originalText=\"Patient Identity Feed\"/></EventIdentification><ActiveParticipant AlternativeUserID=\"11000000000506150000169\" NetworkAccessPointID=\"10.70.65.176\" NetworkAccessPointTypeCode=\"2\" UserID=\"2.16.756.5.30.1.107|2.16.756.5.30.1.107.4.2\" UserIsRequestor=\"true\"><RoleIDCode codeSystemName=\"DCM\" csd-code=\"110153\" originalText=\"Source Role ID\"/></ActiveParticipant><ActiveParticipant NetworkAccessPointID=\"https://api.test.xad.ch/mpi/ws/iti44Service\" NetworkAccessPointTypeCode=\"2\" UserID=\"2.16.756.5.30.1.194|2.16.756.5.30.1.194.3.1\" UserIsRequestor=\"false\"><RoleIDCode codeSystemName=\"DCM\" csd-code=\"110152\" originalText=\"Destination Role ID\"/></ActiveParticipant><AuditSourceIdentification AuditEnterpriseSiteID=\"2.16.756.5.30.1.107.4\" AuditSourceID=\"KSW ddag Navision TEST\"><AuditSourceTypeCode csd-code=\"4\"/></AuditSourceIdentification><ParticipantObjectIdentification ParticipantObjectID=\"1069851^^^&amp;2.16.756.5.30.1.107.4.2.1&amp;ISO\" ParticipantObjectTypeCode=\"1\" ParticipantObjectTypeCodeRole=\"1\"><ParticipantObjectIDTypeCode codeSystemName=\"RFC-3881\" csd-code=\"2\" originalText=\"Patient Number\"/><ParticipantObjectDetail type=\"II\" value=\"Mi4xNi43NTYuNS4zMC4xLjEwNy40LjIuMTA5MDM0MDQ3MDQ2MDE5MDQxLjE2MDU1MTY2NTAyMzkuMjE=\"/></ParticipantObjectIdentification></AuditMessage>\n" "Ereignisaktionen") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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