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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

import Foundation let pattern = #"(numberPinyin":\s*".*)(v)(.*)""# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" ['{"russian": "женщина", "english": "woman, v","numberPinyin": "nv3","typeOfChar":"character","typeOfTranslating":"original"}', '{"chinese": "弯竖左钩", "russian": "вогнутая с крюком влево", "english": "concave with left hook","numberPinyin": "eav","typeOfChar":"stroke","typeOfTranslating":"byStrokes"}', '{"chinese": "弯竖右钩", "russian": "вогнутая с крюком вправо", "english": "concave with right hook","numberPinyin": "vm2","typeOfChar":"stroke","typeOfTranslating":"byStrokes"}'] """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"\1ü\3"# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) print(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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression