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

/
/

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

const regex = /(\/\/ \[\'administrator_start\'\])(.|\n)*(\/\/ \[\'administrator_end\'\])/; // Alternative syntax using RegExp constructor // const regex = new RegExp('(\\\/\\\/ \\[\\\'administrator_start\\\'\\])(.|\\n)*(\\\/\\\/ \\[\\\'administrator_end\\\'\\])', '') const str = ` // ['administrator_start'] if (\$_SESSION["user_group_short"] == "administrator" && \$_SESSION['active'] == 1) { // // //Группа administrator // // ?> <div> Администратор </div> <div id="databoard"> <?php function showTree(\$folder) { /* Получаем полный список файлов и каталогов внутри \$folder */ \$files = scandir(\$folder); foreach (\$files as \$file) { /* Отбрасываем текущий и родительский каталог */ if ((\$file == '.') || (\$file == '..')) { continue; } \$f0 = \$folder . '/' . \$file; //Получаем полный путь к файлу /* Если это директория */ if (is_dir(\$f0)) { /* Выводим, делая заданный отступ, название директории */ echo "<p>" . translate(iconv(mb_detect_encoding(\$file, mb_detect_order(), true), "UTF-8", \$file)) . "</p>"; /* С помощью рекурсии выводим содержимое полученной директории */ showTree(\$f0); } else { /* Если это файл, то просто выводим название файла */ \$name_page = explode(".", iconv(mb_detect_encoding(\$file, mb_detect_order(), true), "UTF-8", \$file)); echo "<a style='text-decoration: none;' href='" . iconv(mb_detect_encoding(\$f0, mb_detect_order(), true), "UTF-8", \$f0) . "'>" . translate(\$name_page[0]) . "</a> "; } } } showTree("../pages/" . \$_SESSION['user_group_short']); ?> </div> <?php } // ['administrator_end'] // ['insert_body']`; const subst = ``; // 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