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

/
/

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @".*?UserID=""(?<UserID>.*?)"".*?UserName=""(?<UserName>.*?)"".*?NetworkAccessPointID=""(?<IPAddress>.*?)"".*?EventDateTime=""(?<DateTime>.*?)"".*?EventOutcomeIndicator=""(?<OutcomeIndicator>.*?)"".*?csd-code=""(?<csd_code>.*?)"".*?AuditEnterpriseSiteID=""(?<Site>.*?)"".*?ParticipantObjectID=""(?<PatientID>.*?)"".*?ParticipantObjectTypeCode=""(?<ObjectTypeCode>.*?)"".*?"; string input = @"<AuditMessage xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xmlns:xsd=""http://www.w3.org/2001/XMLSchema""> <ActiveParticipant UserID=""10361"" UserIsRequestor=""true"" UserName=""Alexander Hardin"" NetworkAccessPointID=""184.190.165.174"" NetworkAccessPointTypeCode=""2"" /> <EventIdentification EventDateTime=""2022-08-15T04:26:37+0000"" EventOutcomeIndicator=""0"" EventActionCode=""R""> <EventID codeSystemName=""DCM"" csd-code=""110110"" originalText=""Patient Record"" /> </EventIdentification> <AuditSourceIdentification AuditSourceID=""Carepointe"" AuditEnterpriseSiteID=""AZ"" /> <ParticipantObjectIdentification ParticipantObjectID="" ParticipantObjectTypeCodeRole=""1"" ParticipantObjectTypeCode=""1"" ParticipantObjectDataLifeCycle=""6""> <ParticipantObjectIDTypeCode>2</ParticipantObjectIDTypeCode> <ParticipantObjectQuery>U0VMRUNUIFVzZXJfSUQsIEZpcnN0TmFtZSwgTGFzdE5hbWUsIENvbXBhbnksIFJvbGVfSUQgRlJPTSB0YmxfdXNlcnMgV0hFUkUgVXNlcl9JRCA9IDp1aWQ=</ParticipantObjectQuery> <ParticipantObjectDetail type=""User_ID"" value=""MTAzNjE="" /> </ParticipantObjectIdentification> <DICOMObjectDescriptionContents> <Anonymized>0</Anonymized> <Encrypted>0</Encrypted> </DICOMObjectDescriptionContents> </AuditMessage>"; Match m = Regex.Match(input, pattern); 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