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

/
/
gm

Test String

Code Generator

Language

Generated Code

$re = '/(?=Violating URL: ).*?(?=$)/m'; $str = 'Site Searched: SomeSite Keywords: OurCompany, lineman Found violations: 3 Infringement Letter: N:\\Curriculum\\Copyright\\Infringement\\Infringement Letters\\Infringement letters\\SomeSite\\Infringement Copyright Letter SomeSite_06_18_2019_mjf Response Email located: N:\\Curriculum\\Copyright\\Infringement\\Infringement Letters\\Infringement letters\\Reponses\\06_18_19_RE DMCA Notice of Copyright Infringement Item Code: T251LM.K1 Submitter: The Real J. Evans Submitted Date: 8/2/17 URL Title: OurCompany Test 2 Installer/Tech Job Information, Level I – 2nd Ed., Lesson 1 Violating URL: https://www.SomeSite.com/?src_url=https://www.SomeSite.com/#flashcard/view/19827671 Item Code: J221LM.M1 Submitter: The Real J. Evans Submitted Date: 8/2/17 URL Title: OurCompany Test 3 Job Information 1, Level I – 2017 Ed., Lesson 10 Violating URL: https://www.SomeSite.com/?src_url=https://www.SomeSite.com/#flashcard/view/19827673 Item Code: OA2-1LM Submitter: The Real J. Evans Submitted Date: 8/2/17 URL Title: OurCompany Test 2-1 Outside 2nd Year, Level 1, Lesson 2 Violating URL: https://www.SomeSite.com/?src_url=https://www.SomeSite.com/#flashcard/view/19827549 '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($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