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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<PurposeOfUse csd-code=\""(?<ATNAPurposeOfUse>.+?)\"""; string input = @"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> "; RegexOptions options = RegexOptions.Multiline; 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