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

/
/
msi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?smi)^.*tag=""[A-Z]_([A-Z]{2})_(\d{4}).*$"; string substitution = @"CG $1($2)"; string input = @"<?xml version=""1.0""?> -<PEGraphic gridSpaceY=""100"" gridSpaceX=""100"" bkgdImage="" gridColor=""#333333"" paperColor=""#000000"" width=""19600"" height=""14200"" version=""5""> <Font height=""120"" name=""Arial""/> -<Polyline backFill=""yes"" backColor=""#FFFFFF""> <Location right=""6020"" bottom=""12445"" left=""6018"" top=""11741""/> <Pen width=""2"" style=""solid"" color=""#00FF00""/> <Brush style=""hollow"" color=""#00FF00""/> <Point y=""11741"" x=""6019""/> <Point y=""12445"" x=""6019""/> </Polyline> -<Polyline backFill=""yes"" backColor=""#E0E0E0""> <Location right=""3365"" bottom=""12835"" left=""3363"" top=""11741""/> <Pen width=""2"" style=""solid"" color=""#00FF00""/> <Brush style=""hollow"" color=""#00FF00""/> <Point y=""11741"" x=""3364""/> <Point y=""12835"" x=""3364""/> </Polyline> -<Polyline backFill=""yes"" backColor=""#FFFFFF""> <Location right=""4627"" bottom=""6800"" left=""4521"" top=""5100""/> <Pen width=""2"" style=""solid"" color=""#00FF00""/> <Brush style=""hollow"" color=""#00FF00""/> <Datasource stepped=""no"" server=""USFRPVMESPOLYOL"" map=""IP_DIMAP"" field=""VAL"" tag=""p_dc_1730""/> -<Animation on=""yes""> <AnimationRange color=""#666666"" image="" text=""act sp"" max=""0"" min=""0"" index=""1""/> <AnimationRange color=""#00FF00"" image="" text=""act sp"" max=""1"" min=""1"" index=""2""/> </Animation> <Point y=""5100"" x=""4627""/> <Point y=""6800"" x=""4627""/> </Polyline> -<Polyline backFill=""yes"" backColor=""#FFFFFF""> <Location right=""3719"" bottom=""4394"" left=""1918"" top=""3300""/> <Pen width=""2"" style=""solid"" color=""#00FF00""/> <Brush style=""hollow"" color=""#00FF00""/> <Datasource stepped=""no"" server=""USFRPVMESPOLYOL"" map="" field=""VAL"" tag=""P_DC_2103""/> -<Animation on=""yes""> <AnimationRange color=""#666666"" image="" text=""act sp"" max=""0"" min=""0"" index=""1""/> <AnimationRange color=""#00FF00"" image="" text=""act sp"" max=""1"" min=""1"" index=""2""/> </Animation> <Point y=""4394"" x=""3718""/> <Point y=""4098"" x=""3718""/> <Point y=""4098"" x=""1918""/> <Point y=""3300"" x=""1918""/> </Polyline> "; RegexOptions options = RegexOptions.Multiline | RegexOptions.Singleline | RegexOptions.IgnoreCase; Regex regex = new Regex(pattern, options); string result = regex.Replace(input, substitution, 1); } }

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