Regular Expressions 101

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  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
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  • Quantifiers
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  • Character Classes
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  • Substitution
  • A single character of: a, b or c
  • A character except: a, b or c
  • A character in the range: a-z
  • A character not in the range: a-z
  • A character in the range: a-z or A-Z
  • Any single character
  • Alternate - match either a or b
  • Any whitespace character
  • Any non-whitespace character
  • Any digit
  • Any non-digit
  • Any word character
  • Any non-word character
  • Match everything enclosed
  • Capture everything enclosed
  • Zero or one of a
  • Zero or more of a
  • One or more of a
  • Exactly 3 of a
  • 3 or more of a
  • Between 3 and 6 of a
  • Start of string
  • End of string
  • A word boundary
  • Non-word boundary

Regular Expression


Test String

Code Generator

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=\""\"" 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: