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

Code Generator

Language

Generated Code

$re = '/(&amp;)(\'.$Key.\')([^0-9a-zA-Z_])/'; $str = '<?php // Сравниваем Куки с данными if ($_COOKIE[\'login\'] == $admin_login AND $_COOKIE[\'password\'] == md5($admin_pass)) { If (isset($_POST[\'submit\'])){ $date=explode(".", date("d.m.Y")); switch ($date[1]){ case 1: $m=\'января\'; break; case 2: $m=\'февраля\'; break; case 3: $m=\'марта\'; break; case 4: $m=\'апреля\'; break; case 5: $m=\'мая\'; break; case 6: $m=\'июня\'; break; case 7: $m=\'июля\'; break; case 8: $m=\'августа\'; break; case 9: $m=\'сентября\'; break; case 10: $m=\'октября\'; break; case 11: $m=\'ноября\'; break; case 12: $m=\'декабря\'; break; } $createdata = $date[0].\'&nbsp;\'.$m.\',&nbsp;\'.$date[2]; $useradd = \'Admin\'; $name = $_POST[\'amess\']; $useradd = $_POST[\'useradd\']; $text = $_POST[\'mess\']; $textkrat = $_POST[\'opisan\']; $title = $_POST[\'title\']; $description = $_POST[\'description\']; $keyword = $_POST[\'keywords\']; $url = $_POST[\'amessurl\']; $tegs = $_POST[\'tegs\']; ?>'; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php