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

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\\""\d{1,3}cm\\"""; string input = @"""<?xml version=\""1.0\"" standalone=\""no\""?>"", ""<svg xmlns=\""http://www.w3.org/2000/svg\"" version=\""1.1\"" width=\""1250cm\"" height=\""1250cm\"">"", ""<desc>9W43OV00W8JKMA1IJNEYAM1WTG9AZH8K10LC</desc>"", ""<g id=\""HMLW03D1BYIQ\"" fill=\""red\"">"", ""<rect x=\""252cm\"" y=\""252cm\"" width=\""252cm\"" height=\""252cm\""/>"", ""<rect x=\""72cm\"" y=\""72cm\"" width=\""72cm\"" height=\""72cm\""/>"", ""<rect x=\""131cm\"" y=\""131cm\"" width=\""131cm\"" height=\""131cm\""/>"", ""<rect x=\""228cm\"" y=\""228cm\"" width=\""228cm\"" height=\""228cm\""/>"", ""<rect x=\""240cm\"" y=\""240cm\"" width=\""240cm\"" height=\""240cm\""/>"", ""<rect x=\""232cm\"" y=\""232cm\"" width=\""232cm\"" height=\""232cm\""/>"", ""<rect x=\""192cm\"" y=\""192cm\"" width=\""192cm\"" height=\""192cm\""/>"", ""<rect x=\""0cm\"" y=\""0cm\"" width=\""0cm\"" height=\""0cm\""/>"", ""<rect x=\""0cm\"" y=\""0cm\"" width=\""0cm\"" height=\""0cm\""/>"", ""<rect x=\""0cm\"" y=\""0cm\"" width=\""0cm\"" height=\""0cm\""/>"", ""<rect x=\""65cm\"" y=\""65cm\"" width=\""65cm\"" height=\""65cm\""/>"", ""<rect x=\""81cm\"" y=\""81cm\"" width=\""81cm\"" height=\""81cm\""/>"", ""<rect x=\""65cm\"" y=\""65cm\"" width=\""65cm\"" height=\""65cm\""/>"", ""<rect x=\""80cm\"" y=\""80cm\"" width=\""80cm\"" height=\""80cm\""/>"", ""<rect x=\""82cm\"" y=\""82cm\"" width=\""82cm\"" height=\""82cm\""/>"", ""<rect x=\""81cm\"" y=\""81cm\"" width=\""81cm\"" height=\""81cm\""/>"", ""</g>"""; 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