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

Code Generator

Language

Generated Code

import Foundation let pattern = #"http://www\.myurl\.com/\?action=joingiveaway&amp;id=([0-9]+)"# let regex = try! NSRegularExpression(pattern: pattern) let testString = ##""" <DIV> <H2><A style="COLOR: black" href="http://www.myurl.com/?action=viewgiveaways&amp;id=287">New car Giveaway</A></H2></DIV> <DIV style="MARGIN-TOP: 6px">The Winner of this giveaway will win a new car!</DIV> <DIV class=box_round style="BORDER-TOP: red 1px solid; BORDER-RIGHT: red 1px solid; BORDER-BOTTOM: red 1px solid; PADDING-BOTTOM: 8px; PADDING-TOP: 8px; PADDING-LEFT: 8px; BORDER-LEFT: red 1px solid; MARGIN-TOP: 10px; PADDING-RIGHT: 8px"> <DIV><B>Special Requirement : </B></DIV> <DIV style="MARGIN-TOP: 2px">You need to have earned atleast <B style="COLOR: blue">1000 Coins </B>in total to enter this Giveaway </DIV> <DIV style="COLOR: green; MARGIN-TOP: 2px">Your total coin earnings is 21707 </DIV></DIV> <DIV style="MARGIN-TOP: 6px"><B>Entry Fee : 20 Coins</B></DIV> <DIV style="MARGIN: 6px"><A class=cssbutton style="COLOR: white" href="http://www.myurl.com/?action=joingiveaway&amp;id=287">Enter Giveaway</A><BR><SMALL>You have 0 entries</SMALL></DIV></DIV> <DIV style="FLOAT: right"> <DIV>Group : Everyone</DIV> <DIV>Multiple Entries : No</DIV> <DIV>Total Entries : <A href="http://www.myurl.com/?action=viewentries&amp;giveawayid=287">4</A></DIV> <DIV>Max Entries : 100</DIV> <DIV>Start Date : Jan 23 2013</DIV> <DIV><A href="http://www.myurl.com/index.php?action=faq#coins" target=_blank>How To Earn Coins?</A></DIV></DIV> <DIV style="CLEAR: both"></DIV></DIV></DIV></DIV> <DIV class=index-left style="FLOAT: right; PADDING-TOP: 15px; PADDING-RIGHT: 23px"> <DIV class=left-section> """## let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } 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