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 = '/(\[)(\d+)(\].*\')(.+)(\')/m'; $str = ' [1] = 0 \'NumProgPlc\' [2] = 3 \'PadCode\' [3] = 2 \'TablePos\' [4] = 1 \'CurrentTool\' [5] = 0 \'Loc. Override\' [10] = .200000 \'PlaceDelay\' [11] = .300000 \'PickDelay\' [12] = .150000 \'ChamfersChkDelay\' [15] = -107.575500 \'xLpos\' [16] = 398.586304 \'yLpos\' [17] = 277.373779 \'zLpos\' [18] = 90.000000 \'RotApproNasAlim\' [21] = 53 \'PR Offset Tavola\' [22] = 110 \'PR Sopra Tavola\' [23] = 267 \'DO Magnete ON\' [24] = 268 \'DO Magnete OFF\' [25] = 243 \'DI PresPastTav\' [26] = 247 \'DI PezNoPrelTav\' [27] = 1 \'DO Soffio\' [28] = 111 \'PR Tavola+20\' [29] = 112 \'PR Tavola\' [30] = 0 \'_Prelevato\' [31] = 0 \'_ScartoTav\' [32] = 0 \'_ScartoCtrlUs\' [33] = 0 \'_ScambioTav\' [34] = 0 \'_CaricoTav\' [35] = 1 \'FlagMemPtoNasAli\' [36] = 244 \'DO PezPrelTav\' [37] = 243 \'DO PezScamTav\' [38] = 242 \'DO PezDepoTav\' [39] = 132 \'PR Tavola+50\' [45] = 229 \'DI PezPrelNas\' [46] = 1 \'OK_PRL\' [50] = 1 \'PrioritaNas\' [51] = 0 \'CaricoNas\' [55] = 0 \'Conveyor2Rot180\' [200] = 3.216000 \'TC\' '; $subst = "R\t\2\t\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