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

/
/
igm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<tagname((.|\n)(?!string))*?<\/tagname>"; string input = @"<?xml version=""1.0"" encoding=""utf-8""?> <OdfBody Source=""IDS"" DocumentCode=""EQ0000000"" Serial=""869"" Time=""104139151"" CompetitionCode=""PG2016"" Date=""2016-09-02"" FeedFlag=""P"" LogicalDate=""2016-09-02"" DocumentType=""DT_PARTIC"" Version=""3"" > <Competition Code=""PG2016""> <Participant Parent=""1057257"" MainFunctionId=""AA01"" OlympicSolidarity=""N"" Organisation=""AUT"" Code=""1057257"" BirthDate=""1977-12-15"" Nationality=""AUT"" Status=""ACTIVE"" TVName=""Michael Martin KNAUDER"" GivenName=""Michael Martin"" Gender=""M"" TVInitialName=""M.M. KNAUDER"" FamilyName=""KNAUDER"" PrintName=""KNAUDER Michael Martin"" PrintInitialName=""KNAUDER MM"" Current=""true""> <Discipline IFId=""10081843"" Code=""EQ""> <RegisteredEvent Event=""001"" Class=""GIA"" Gender=""X""> <EventEntry Value=""H014452"" Type=""ENTRY"" Code=""HORSE_ID""/> <EventEntry Value=""P 7"" Type=""ENTRY"" Code=""PROFILE""/> </RegisteredEvent> <RegisteredEvent Event=""401"" Class=""GIA"" Gender=""X""> <EventEntry Value=""H014452"" Type=""ENTRY"" Code=""HORSE""/> <EventEntry Value=""P 7"" Type=""ENTRY"" Code=""PROFILE""/> </RegisteredEvent> <RegisteredEvent Event=""420"" Class=""GIA"" Gender=""X""> <EventEntry Value=""H014452"" Type=""ENTRY"" Code=""HORSE_ID""/> <EventEntry Value=""P 7"" Type=""ENTRY"" Code=""PROFILE""/> </RegisteredEvent> </Discipline> </Participant> <Participant Parent=""1063065"" MainFunctionId=""TM_OFFIC"" OlympicSolidarity=""N"" Organisation=""CZE"" Code=""1063065"" BirthDate=""1974-10-28"" Nationality=""CZE"" Status=""ACTIVE"" TVName=""Lenka MATOSKOVA"" GivenName=""Lenka"" Gender=""W"" TVInitialName=""L. MATOSKOVA"" FamilyName=""MATOSKOVA"" PrintName=""MATOSKOVA Lenka"" PrintInitialName=""MATOSKOVA L"" Current=""true""> <Discipline Code=""EQ""/> </Participant> <Participant Parent=""1096278"" MainFunctionId=""AA01"" OlympicSolidarity=""N"" Organisation=""AUT"" Code=""1096278"" BirthDate=""1995-09-24"" Nationality=""AUT"" Status=""ACTIVE"" TVName=""Julia SCIANCALEPORE"" GivenName=""Julia"" Gender=""W"" TVInitialName=""J. SCIANCALEPORE"" FamilyName=""SCIANCALEPORE"" PrintName=""SCIANCALEPORE Julia"" PrintInitialName=""SCIANCALEPORE J"" Current=""true""> <Discipline IFId=""10108391"" Code=""EQ""> <RegisteredEvent Event=""001"" Class=""GIA"" Gender=""X""> <EventEntry Value=""H014366"" Type=""ENTRY"" Code=""HORSE_ID""/> <EventEntry Value=""P 12a"" Type=""ENTRY"" Code=""PROFILE""/> </RegisteredEvent> <RegisteredEvent Event=""401"" Class=""GIA"" Gender=""X""> <EventEntry Value=""H014366"" Type=""ENTRY"" Code=""HORSE""/> <EventEntry Value=""P 12a"" Type=""ENTRY"" Code=""PROFILE""/> </RegisteredEvent> <RegisteredEvent Event=""420"" Class=""GIA"" Gender=""X""> <EventEntry Value=""H014366"" Type=""ENTRY"" Code=""HORSE_ID""/> <EventEntry Value=""P 12a"" Type=""ENTRY"" Code=""PROFILE""/> </RegisteredEvent> </Discipline> </Participant> </Competition> </OdfBody>"; RegexOptions options = RegexOptions.IgnoreCase | 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