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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<EventTypeCode csd-code=\""(?<myEventTypeCode>\w{3}\-\d{2})\"""; string input = @" <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> "; RegexOptions options = RegexOptions.Singleline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx