Regular Expressions 101

Save & Share

  • Regex Version: ver. 1
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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 = #"^.*\\r\\n\|\*(Task 1)\*\|(.*)\|(.*)\|(.*)\|(.*)\|\\r\\n\|\*(Task 2)\*\|(.*)\|(.*)\|(.*)\|(.*)\|\\r\\n\|\*(Task 3)\*\|(.*)\|(.*)\|(.*)\|(.*)\|\\r\\n\|\*(Task 4)\*\|(.*)\|(.*)\|(.*)\|(.*)\|$"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #"|| ||Du Date||Done on||OK/NOK||Remarks||\r\n|*Task 1*| | | | |\r\n|*Task 2*| | | | |\r\n|*Task 3*| | | | |\r\n|*Task 4*| 15/03/23| | | See document X|"# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"{"ACTION":[{"TITLE":"$1","DUE DATE":"$2","DONE ON":"$3","NOTE":"$5"},{"TITLE":"$6","DUE DATE":"$7","DONE ON":"$8","NOTE":"$10"},{"TITLE":"$11","DUE DATE":"$12","DONE ON":"$13","NOTE":"$15"},{"TITLE":"$16","DUE DATE":"$17","DONE ON":"$8","NOTE":"$20"}]}"# 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