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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

import Foundation let pattern = #"^(?<year>\d{4})[-\/](?<month>0[1-9]|1[0-2])[-\/](?<day>0[1-9]|[1-2][0-9]|3[0-1])(?:[T\s](?:(?<hour>0[0-9]|1[0-9]|2[0-4]):(?<minute>\d{2}):(?<second>\d{2})(?:\.(?<nano>\d+))?))?(?:(?<offset>[Zz]|(?:[+-])(?:[01]\d|2[0-3])(?::?[0-5]\d)?)?)$"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" 2020-12-01T12:13:51.123+02:00 2020-12-01T12:13:51.123+0200 2020-12-01T12:13:51.123Z 2020-12-01T12:13:51.123 2020-12-01T12:13:51.123341512+02:00 2020-12-01T12:13:51.123341512+0200 2020-12-01T12:13:51.123341512Z 2020-12-01T12:13:51.123341512 2020-12-01T12:13:51+02:00 2020-12-01T12:13:51+0200 2020-12-01T12:13:51Z 2020-12-01T12:13:51 2020-12-01 12:13:51.123 +02:00 2020-12-01 12:13:51.123 +0200 2020-12-01 12:13:51.123Z 2020-12-01 12:13:51.123 2020-12-01 12:13:51.123341512 +02:00 2020-12-01 12:13:51.123341512 +0200 2020-12-01 12:13:51.123341512Z 2020-12-01 12:13:51.123341512 2020-12-01 12:13:51+02:00 2020-12-01 12:13:51+0200 2020-12-01 12:13:51Z 2020-12-01 12:13:51 2020-12-01+02:00 2020-12-01+0200 2020-12-01Z 2020-12-01 2020/12/01T12:13:51.123+02:00 2020/12/01T12:13:51.123+0200 2020/12/01T12:13:51.123Z 2020/12/01T12:13:51.123 2020/12/01T12:13:51.123341512+02:00 2020/12/01T12:13:51.123341512+0200 2020/12/01T12:13:51.123341512Z 2020/12/01T12:13:51.123341512 2020/12/01T12:13:51+02:00 2020/12/01T12:13:51+0200 2020/12/01T12:13:51Z 2020/12/01T12:13:51 2020/12/01+02:00 2020/12/01+0200 2020/12/01Z 2020/12/01 2039/15/23 2923/09/12 2023/23/51 2020-12-01T00:13:51 2020-12-01T01:13:51 2020-12-01T10:13:51 2020-12-01T19:13:51 2020-12-01T20:13:51 2020-12-01T24:13:51 """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"$1-$2-$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