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 = @"(^[a-zA-Z._-]+)\(([0-9]+)\) : (error.*)"; string input = @".\include\intentionally_initally_empty.txt 1 File(s) copied // Compiling galileo.sma ... Current time is: 15:26:16,93 - 11/09/2016 Welcome to the AMX Mod X 1.8.1-300 Compiler. Copyright (c) 1997-2013 ITB CompuPhase, AMX Mod X Team galileo.sma(1026) : error 017: undefined symbol ""nextmap_plugin_init"" galileo.sma(1032) : error 017: undefined symbol ""register_dictionary_colored"" galileo.sma(1208) : error 017: undefined symbol ""nomination_clearAll"" gali_leo.sma(1288) : error 017: undefined symbol ""get_realplayersnum"" galileo.sma(1455) : error 017: undefined symbol ""serverChangeLevel"" galileo.sma(1524) : error 017: undefined symbol ""saveEndGameLimits"" gali-leo.sma(1558) : error 017: undefined symbol ""map_getNext"" galileo.sma(1572) : error 017: undefined symbol ""map_getNext"" galileo.sma(1620) : error 017: undefined symbol ""saveCurrentMapCycleSetting"" galileo.sma(2294) : error 017: undefined symbol ""cancelVoting"" galileo.sma(2312) : error 017: undefined symbol ""cancelVoting"" galileo.sma(2389) : error 017: undefined symbol ""map_getMinutesElapsedInteger"" galileo.sma(2389) : error 017: undefined symbol ""saveEndGameLimits"" galileo.sma(2390) : error 017: undefined symbol ""saveEndGameLimits"" galileo.sma(2391) : error 017: undefined symbol ""saveEndGameLimits"" galileo.sma(2392) : error 017: undefined symbol ""saveEndGameLimits"" galileo.sma(2942) : error 017: undefined symbol ""get_realplayersnum"" galileo.sma(2954) : error 017: undefined symbol ""get_realplayersnum"" galileo.sma(3062) : error 017: undefined symbol ""get_realplayersnum"" galileo.sma(3169) : error 017: undefined symbol ""map_isInMenu"" galileo.sma(3352) : error 017: undefined symbol ""get_realplayersnum"" galileo.sma(3425) : error 017: undefined symbol ""getPlayerNominationMapIndex"" galileo.sma(3471) : error 017: undefined symbol ""get_realplayersnum"" galileo.sma(3545) : error 017: undefined symbol ""color_print"" galileo.sma(3551) : error 017: undefined symbol ""color_print"" galileo.sma(3627) : error 017: undefined symbol ""color_print"" Compilation aborted. 26 Errors. Could not locate output file compiled/galileo.amx (compile failed). Took 0:00:01,54 seconds to run this script. [Finished in 2.3s]"; 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