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

/
/
g

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #"\s+([a-zA-Z-]+)=([a-zA-Z0-9-]+)"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" <p class=MsoNormal align=center style='text-align:center'><b><span style='font-size:24.0pt;font-family:Calibri;color:maroon'>Electronic Subscriptions</span></b></p> <table class=MsoNormalTable border=0 cellpadding=0 align=left width="100%" style='width:100.0%;mso-cellspacing:1.5pt;background:white;mso-table-lspace: 9.0pt;margin-left:6.75pt;mso-table-rspace:9.0pt;margin-right:6.75pt; mso-table-anchor-vertical:paragraph;mso-table-anchor-horizontal:column; mso-table-left:left;mso-padding-alt:0in 0in 0in 0in'> <tr style='mso-yfti-irow:0;mso-yfti-firstrow:yes;mso-yfti-lastrow:yes; height:662.25pt'> <td valign=top style='padding:15.0pt 15.0pt 15.0pt 15.0pt;height:662.25pt'> <p class=MsoNormal style='mso-element:frame;mso-element-frame-hspace:9.0pt; mso-element-wrap:around;mso-element-anchor-vertical:paragraph;mso-element-anchor-horizontal: column;mso-height-rule:exactly'><span style='font-size:11.0pt;font-family: Calibri;color:black'>&nbsp;</span></p> <p class=MsoNormal style='mso-element:frame;mso-element-frame-hspace:9.0pt; mso-element-wrap:around;mso-element-anchor-vertical:paragraph;mso-element-anchor-horizontal: column;mso-height-rule:exactly'><span style='font-size:11.0pt;font-family: Calibri;color:black'> """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #" \1="\2""# 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