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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^(\+ *|- *)?((?!0+)\d*?|(?!0{2,})\d*?\.(?!0+)\d*?)('|"")$|^(\+ *|- *)? *(?!0+)\d+?' *-? *(\d+?|\d*?\.\d*?)""$|^((\+ *|- *)?((?!0+)|0 )\d*? *(?!0+)\d+?\/(?!0+)\d+?('|""))$"; string input = @" - + - x 20'-4"" + 20' - 20' 20'3"" 20'-3"" 20' - 40"" -20'-20"" 20'00"" 20.45"" 20.45' 00.45' 00.45"" 00"" 00' +20' - 0.45"" 20' - .45"" .20'-4"" 0.30'-4"" 20' 20'P 20"" 20""P 0.20' .20' a' b"" - 20 1/2' + 20 22/128"" 20 0/2"" 20 00/12' -1/2"" + 1/2' 0/2"" 00/22"" + 01/2"" 23 00/30' 23 12/03' 23 02/20"" 0 2/3' 00 2/3' - 11 2/3' 2 22' 2 22/03' 2 3/2 23 00/30 23 12/03 23 02/20 23/34"" 23/23.4"" asf sf"" "; 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