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

/
/
gs

Test String

Code Generator

Language

Generated Code

const regex = /<EventTypeCode csd-code=\"(?<myEventTypeCode>\w{3}\-\d{2})\"/gs; // Alternative syntax using RegExp constructor // const regex = new RegExp('<EventTypeCode csd-code=\\"(?<myEventTypeCode>\\w{3}\\-\\d{2})\\"', 'gs') const str = ` <85>1 2020-03-22T18:00:44.389Z hcoxadepdtest01-app06-icwpxs01.net.swisscom-health.it icw-chr 48261 IHE+RFC-3881 - <?xml version="1.0" encoding="UTF-8"?> <AuditMessage> <EventIdentification EventActionCode="E" EventDateTime="2020-03-22T18:00:44.388Z" EventOutcomeIndicator="0"> <EventID csd-code="110112" codeSystemName="DCM" originalText="Query" /> <EventTypeCode csd-code="ITI-18" codeSystemName="IHE Transactions" originalText="Registry Stored Query" /> </EventIdentification> <ActiveParticipant UserID="2f66e56b-7d4e-4fb3-86ad-ba53a2208b5f" AlternativeUserID="48261" UserName="" UserIsRequestor="true" NetworkAccessPointID="10.1.44.2" NetworkAccessPointTypeCode="2"> <RoleIDCode csd-code="110153" codeSystemName="DCM" originalText="Source Role ID" /> </ActiveParticipant> <ActiveParticipant UserID="1111111111139" UserName="Gabriela Brunner-Mühlethaler" UserIsRequestor="true"> <RoleIDCode csd-code="HCP" codeSystemName="2.16.756.5.30.1.127.3.10.6" originalText="Behandelnde(r)" /> </ActiveParticipant> <ActiveParticipant UserID="Internal" UserIsRequestor="false"> <RoleIDCode csd-code="110152" codeSystemName="DCM" originalText="Destination Role ID" /> </ActiveParticipant> <AuditSourceIdentification AuditEnterpriseSiteID="2.16.756.5.30.1.194" AuditSourceID="hcoxadepdtest01-app06-icwpxs01"> <AuditSourceTypeCode csd-code="9" codeSystemName="DCM" originalText="Other" /> </AuditSourceIdentification> <ParticipantObjectIdentification ParticipantObjectID="304909^^^&amp;2.16.756.5.30.1.194.3.1.1&amp;ISO" ParticipantObjectTypeCode="1" ParticipantObjectTypeCodeRole="1"> <ParticipantObjectIDTypeCode csd-code="2" codeSystemName="RFC-3881" originalText="Patient Number" /> </ParticipantObjectIdentification> <ParticipantObjectIdentification ParticipantObjectID="urn:uuid:10b545ea-725c-446d-9b95-8aeb444eddf3" ParticipantObjectTypeCode="2" ParticipantObjectTypeCodeRole="24"> <ParticipantObjectIDTypeCode csd-code="ITI-18" codeSystemName="IHE Transactions" originalText="Registry Stored Query" /> <ParticipantObjectQuery>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</ParticipantObjectQuery> <ParticipantObjectDetail type="QueryEncoding" value="VVRGLTg=" /> <ParticipantObjectDetail type="urn:ihe:iti:xca:2010:homeCommunityId" value="Mi4xNi43NTYuNS4zMC4xLjE5NA==" /> </ParticipantObjectIdentification> </AuditMessage> `; // 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