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

use strict; my $str = '2677 <85>1 2021-01-20T11:59:04+00:00 localhost icw-chr 1436 IHE+RFC-3881 - <?xml version="1.0" encoding="UTF-8"?><AuditMessage><EventIdentification EventActionCode="R" EventDateTime="2021-01-20T11:59:04.678Z" EventOutcomeIndicator="8"><EventID csd-code="110106" codeSystemName="DCM" originalText="Export" /><EventTypeCode csd-code="ITI-43" codeSystemName="IHE Transactions" originalText="Retrieve Document Set" /><PurposeOfUse csd-code="NORM" codeSystemName="2.16.756.5.30.1.127.3.10.5" originalText="Normal Access" /></EventIdentification><ActiveParticipant UserID="https://api.test.xad.ch/pxs/webservices/xca/initiatingGateway/iti43RetrieveDocuments" UserName="svrz1975.spital.so.ch" UserIsRequestor="false" NetworkAccessPointID="10.250.76.81" NetworkAccessPointTypeCode="2"><RoleIDCode csd-code="110153" codeSystemName="DCM" originalText="Source Role ID" /></ActiveParticipant><ActiveParticipant UserID="&lt;7601003961638@xua.hin.ch&gt;" UserName="&lt;7601003961638@xua.hin.ch&gt;" UserIsRequestor="true"><RoleIDCode csd-code="HCP" codeSystemName="2.16.756.5.30.1.127.3.10.6" originalText="Behandelnde(r)" /></ActiveParticipant><ActiveParticipant UserID="7601003961638" UserName="Marco Studer" UserIsRequestor="true"><RoleIDCode csd-code="HCP" codeSystemName="2.16.756.5.30.1.127.3.10.6" originalText="Behandelnde(r)" /></ActiveParticipant><ActiveParticipant UserID="http://www.w3.org/2005/08/addressing/anonymous" AlternativeUserID="1436" UserIsRequestor="false" NetworkAccessPointID="api.test.xad.ch" NetworkAccessPointTypeCode="1"><RoleIDCode csd-code="110152" codeSystemName="DCM" originalText="Destination Role ID" /></ActiveParticipant><AuditSourceIdentification AuditEnterpriseSiteID="2.16.756.5.30.1.194" AuditSourceID="t01-x-chrapp-1"><AuditSourceTypeCode csd-code="9" codeSystemName="DCM" originalText="Other" /></AuditSourceIdentification><ParticipantObjectIdentification ParticipantObjectID="761337610339478800^^^&amp;2.16.756.5.30.1.127.3.10.3&amp;ISO" ParticipantObjectTypeCode="1" ParticipantObjectTypeCodeRole="1"><ParticipantObjectIDTypeCode csd-code="2" codeSystemName="RFC-3881" originalText="Patient Number" /></ParticipantObjectIdentification><ParticipantObjectIdentification ParticipantObjectID="2.25.319915379891245844588550626280213087638" ParticipantObjectTypeCode="2" ParticipantObjectTypeCodeRole="3"><ParticipantObjectIDTypeCode csd-code="9" codeSystemName="RFC-3881" originalText="Report Number" /><ParticipantObjectDetail type="Repository Unique Id" value="Mi4xNi43NTYuNS4zMC4xLjE5NC4zLjMuMg==" /><ParticipantObjectDetail type="ihe:homeCommunityID" value="dXJuOm9pZDoyLjE2Ljc1Ni41LjMwLjEuMTk0" /></ParticipantObjectIdentification></AuditMessage> '; my $regex = qr/<PurposeOfUse csd-code=\"(?<ATNAPurposeOfUse>.+?)\"/mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html