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

/
/
gi

Test String

Code Generator

Generated Code

const regex = /[\r\n]+\s*\/\/.*TODO:+.*/gi; // Alternative syntax using RegExp constructor // const regex = new RegExp('[\\r\\n]+\\s*\\\/\\\/.*TODO:+.*', 'gi') const str = `angular .module('mdKeyboard', ['material.components.bottomSheet']) .directive('mdKeyboard', MdKeyboardDirective) .provider('\$mdKeyboard', MdKeyboardProvider); function MdKeyboardDirective(\$mdKeyboard, \$mdBottomSheet, \$timeout, \$injector, \$log) { return { restrict: 'A', require: '?ngModel', scope: { clickOutsideToClose: '=', preserveScope: '=', showInMobile: '=' }, link: function (scope, element, attrs, ngModelCtrl) { if (!ngModelCtrl) { return; } var bottomSheet; // Don't show virtual keyboard in mobile devices (default) //TODO: test detection and reimplement if neccessary //TODO: dissolve dependency to UAParser if possible / use angular or material utils if (\$injector.has('UAParser')) { var UAParser = \$injector.get('UAParser'); var results = new UAParser().getResult(); var isMobile = results.device.type === 'mobile' || results.device.type === 'tablet'; isMobile = isMobile || (results.os && (results.os.name === 'Android')); isMobile = isMobile || (results.os && (results.os.name === 'iOS')); isMobile = isMobile || (results.os && (results.os.name === 'Windows Phone')); isMobile = isMobile || (results.os && (results.os.name === 'Windows Mobile')); if (isMobile && attrs.showInMobile !== true) { return; } } /* ngVirtualKeyboardService.attach(elements[0], scope.config, function() { \$timeout(function() { ngModelCtrl.\$setViewValue(elements[0].value); }); }); */ \$log.debug(attrs); element .bind('focus', showKeyboard) .bind('blur', hideKeyboard); function showKeyboard() { \$log.info('showKeyboard'); bottomSheet = \$mdBottomSheet .show({ template: '<md-bottom-sheet class="md-grid" layout="column" ng-cloak>{{keyboard}}</md-bottom-sheet>', controller: KeyboardController, clickOutsideToClose: attrs.clickOutsideToClose || false, preserveScope: attrs.preserveScope || true }) .then(function () { }); } function hideKeyboard() { \$log.info('hideKeyboard'); if (bottomSheet) { \$mdBottomSheet.hide(); delete bottomSheet; } } function KeyboardController(\$scope, \$mdBottomSheet) { \$scope.keyboard = 'TEST'; } // open bottomsheet with keyboard on focus TODO: and without backdrop scope.keyboard = 'test'; // When navigation force destroys an interimElement, then // listen and \$destroy() that interim instance... scope.\$on('\$destroy', function () { \$mdKeyboard.destroy(); }); } }; } function MdKeyboardProvider(\$\$interimElementProvider) { return \$\$interimElementProvider('\$mdKeyboard') .setDefaults({ options: keyboardDefaults }); function keyboardDefaults() { return { themable: true, layout: defaultLayout }; function defaultLayout() { // get default language return 'en-us'; } } } `; // 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