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

/
/
g

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

const regex = /(\[.*\])(=>?)\s+(\w+[\(\)\d+\.]+)\s+?(\".*\"|\{[\s\w]+\})?/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(\\[.*\\])(=>?)\\s+(\\w+[\\(\\)\\d+\\.]+)\\s+?(\\".*\\"|\\{[\\s\\w]+\\})?', 'g') const str = `array(40) { ["HTTP_AUTHORIZATION"]=> string(0) "" ["HTTP_HOST"]=> string(12) "galtrade.loc" ["HTTP_CONNECTION"]=> string(10) "keep-alive" ["HTTP_PRAGMA"]=> string(8) "no-cache" ["HTTP_CACHE_CONTROL"]=> string(8) "no-cache" ["HTTP_UPGRADE_INSECURE_REQUESTS"]=> string(1) "1" ["HTTP_USER_AGENT"]=> string(142) "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.109 YaBrowser/19.3.0.2485 Yowser/2.5 Safari/537.36" ["HTTP_ACCEPT"]=> string(85) "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8" ["HTTP_ACCEPT_ENCODING"]=> string(13) "gzip, deflate" ["HTTP_ACCEPT_LANGUAGE"]=> string(11) "ru,en;q=0.9" ["HTTP_COOKIE"]=> string(59) "fdafa396c9597e51e294ef0cc64573a0=c0ntndm6dh8bg3vk901nrs1a05" ["PATH"]=> string(502) "c:\\ospanel\\modules\\php\\PHP-5.6\\ext;c:\\ospanel\\modules\\php\\PHP-5.6\\pear;c:\\ospanel\\modules\\php\\PHP-5.6\\pear\\bin;c:\\ospanel\\modules\\php\\PHP-5.6;c:\\ospanel\\modules\\imagemagick;c:\\ospanel\\modules\\wget\\bin;c:\\ospanel\\modules\\git;c:\\ospanel\\modules\\git\\bin;c:\\ospanel\\modules\\git\\mingw\\bin;c:\\ospanel\\modules\\git\\cmd;c:\\ospanel\\modules\\database\\MySQL-5.6\\bin;c:\\ospanel\\modules\\http\\Apache-2.4\\bin;c:\\ospanel\\modules\\http\\Apache-2.4;C:\\Windows\\system32;C:\\Windows;C:\\Windows\\system32\\Wbem;C:\\Windows\\SysWOW64" ["SystemRoot"]=> string(10) "C:\\Windows" ["COMSPEC"]=> string(27) "C:\\Windows\\system32\\cmd.exe" ["PATHEXT"]=> string(53) ".COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC" ["WINDIR"]=> string(10) "C:\\Windows" ["SERVER_SIGNATURE"]=> string(0) "" ["SERVER_SOFTWARE"]=> string(6) "Apache" ["SERVER_NAME"]= string(12) "galtrade.loc" ["SERVER_ADDR"]=> string(9) "127.0.0.1" ["SERVER_PORT"]=> string(2) "80" ["REMOTE_ADDR"]=> string(9) "127.0.0.1" ["DOCUMENT_ROOT"]=> string(23) "H:/Domains/galtrade.loc" ["REQUEST_SCHEME"]=> string(4) "http" ["CONTEXT_PREFIX"]=> string(0) "" ["CONTEXT_DOCUMENT_ROOT"]=> string(23) "H:/Domains/galtrade.loc" ["SERVER_ADMIN"]=> string(18) "[no address given]" ["SCRIPT_FILENAME"]=> string(33) "H:/Domains/galtrade.loc/index.php" ["REMOTE_PORT"]=> string(5) "45846" ["GATEWAY_INTERFACE"]=> string(7) "CGI/1.1" ["SERVER_PROTOCOL"]=> string(8) "HTTP/1.1" ["REQUEST_METHOD"]=> string(3) "GET" ["QUERY_STRING"]=> string(0) "" ["REQUEST_URI"]=> string(1) "/" ["SCRIPT_NAME"]=> string(10) "/index.php" ["PHP_SELF"]=> string(10) "/index.php" ["REQUEST_TIME_FLOAT"]=> float(1552820558.246) ["REQUEST_TIME"]=> int(1552820558) ["argv"]=> array(0) {sddsdsd } ["argc"]= int(0) }`; const subst = `<i>$1</i><i>$2</i><i>$3</i><i>$4</i>`; // The substituted value will be contained in the result variable const result = str.replace(regex, subst); console.log('Substitution result: ', result);

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