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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"AnumeroSequencial=\d{7}"; string substitution = @"1234569-19.2009.7.19.1009"; string input = @"AJAXREQUEST=_viewRoot&fPP%3Aj_id139%3AnomeParte=&fPP%3Aj_id148%3AoutrosNomesAlcunha=&fPP%3Aj_id157%3AnomeAdvogado=&tipoMascaraDocumento=on&fPP%3AdpDec%3AdocumentoParte=&fPP%3AnumeroProcesso%3AnumeroSequencial=0001252&fPP%3AnumeroProcesso%3AnumeroDigitoVerificador=13&fPP%3AnumeroProcesso%3AAno=2021&fPP%3AnumeroProcesso%3AramoJustica=5&fPP%3AnumeroProcesso%3ArespectivoTribunal=07&fPP%3AnumeroProcesso%3ANumeroOrgaoJustica=8923&fPP%3AprocessoReferenciaDecoration%3AhabilitarMascaraProcessoReferencia=true&fPP%3AprocessoReferenciaDecoration%3AIdProcessoReferenciaComMascaraDecoration%3AIdProcessoReferenciaComMascara=&fPP%3Aj_id225%3Aassunto=&fPP%3Aj_id234%3AclasseJudicial=&fPP%3Aj_id243%3AnumeroDocumento=&fPP%3AdecorationDados%3AnumeroOAB=&fPP%3AdecorationDados%3AletraOAB=&fPP%3AdecorationDados%3AufOABCombo=org.jboss.seam.ui.NoSelectionConverter.noSelectionValue&fPP%3AjurisdicaoComboDecoration%3AjurisdicaoCombo=org.jboss.seam.ui.NoSelectionConverter.noSelectionValue&fPP%3AorgaoJulgadorComboDecoration%3AorgaoJulgadorCombo=org.jboss.seam.ui.NoSelectionConverter.noSelectionValue&fPP%3AdataAutuacaoDecoration%3AdataAutuacaoInicioInputDate=&fPP%3AdataAutuacaoDecoration%3AdataAutuacaoInicioInputCurrentDate=10%2F2022&fPP%3AdataAutuacaoDecoration%3AdataAutuacaoFimInputDate=&fPP%3AdataAutuacaoDecoration%3AdataAutuacaoFimInputCurrentDate=10%2F2022&fPP%3AvalorDaCausaDecoration%3AvalorCausaInicial=&fPP%3AvalorDaCausaDecoration%3AvalorCausaFinal=&fPP%3Aj_id384%3AmovimentacaoProcessualSuggest=&fPP%3Aj_id384%3Aj_id395_selection=&fPP=fPP&autoScroll=&javax.faces.ViewState=j_id3&fPP%3Aj_id402=fPP%3Aj_id402&AJAX%3AEVENTS_COUNT=1&"; RegexOptions options = RegexOptions.Multiline; Regex regex = new Regex(pattern, options); string result = regex.Replace(input, substitution); } }

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