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 = @"ActiveParticipant.*?\sUserID=\""+?(?<atnaUserID>[^\""]+)\"".+?UserIsRequestor=\""true\"""; string input = @"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"; 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