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

/
/
gs

Test String

Code Generator

Language

Generated Code

const regex = /ActiveParticipant.*?\sUserID=\"+?(?<atnaUserID>[^\"]+)\".+?UserIsRequestor=\"true\"/gs; // Alternative syntax using RegExp constructor // const regex = new RegExp('ActiveParticipant.*?\\sUserID=\\"+?(?<atnaUserID>[^\\"]+)\\".+?UserIsRequestor=\\"true\\"', 'gs') const 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> Ereignisaktionen`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions