Regular Expressions 101

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  • Substitution
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  • Unit Tests (2)

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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

$re = '/(\b\d{8})(\d{6}Z)\b/'; $str = '20150624145707Z 20150603182904Z 20150421163629Z 20140529152951Z 20091015212450Z 20140428144528Z 20081009222929Z 20150817231245Z 20150420184902Z 20140428143953Z 20150315070002Z 20150315070003Z 20150212154444Z 20150527165706Z 19970205203358Z 20150413180400Z 20150924180348Z 20030823025726Z 20150423223718Z 20141022171412Z 20150412232614Z 20070505011754Z 20140428144155Z 20141231221928Z 20150305150408Z 20060103155521Z 20131114224409Z 20150910000720Z 20150831151016Z '; $subst = "$1"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$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 PHP, please visit: http://php.net/manual/en/ref.pcre.php