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

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(?<="name": ")(.+)(",\n\s+"war_memorials": ")(.*?\1,)(.*?)(,.*)(?=",)/m'; $str = '"properties": { "cartodb_id": 2, "sortcode": 3, "pop2011": 612431, "pop2002": 652625, "pop1992": 681206, "pop1977": 631918, "pop1966": 529833, "pop1956": 483741, "pop1948": 448964, "regionid": 3, "countycode": 38, "countyid": 3, "region": "Sud", "mnemonic": "AG", "name": "Argeș", "war_memorials": "București,132,Alba,145,Brașov,151,Covasna,100,Harghita,188,Mureș,363,Sibiu,165,Bacău,188,Botoșani,149,Iași,246,Neamț,235,Suceava,219,Vaslui,212,Bihor,199,Bistrița-Năsăud,120,Cluj,186,Maramureș,,Satu Mare,119,Sălaj,79,Brăila,47,Buzău,188,Constanța,89,Galați,,Tulcea,87,Vrancea,76,Argeș,252,Călărași,115,Dâmbovița,191,Giurgiu,180,Ialomița,113,Prahova,162,Teleorman,202,Dolj,212,Gorj,154,Mehedinți,110,Olt,163,Vâlcea,185,Arad,233,Caraș-Severin,176,Hunedoara,118,Timiș,321", "version": "2016-03-10T00:00:00Z", "comune": 95, "orase": "4" } } '; $subst = "\1\2\4"; $result = preg_replace($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