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

/
/
gim

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #"<iframe.*?(width="[0-9]*")?\.?(height="[0-9]*")?\.*?src=".*?youtube\.com\/embed\/(\w*\-?\w*).*?(width="[0-9]*")?\.?(height="[0-9]*")?\.*?><\/iframe>"# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive]) let testString = #""" <iframe width="123" height="237"src="http://www.youtube.com/embed/IMtG_n1FpgA" frameborder="0" allowfullscreen></iframe> <iframe width="560" height="315" src="https://www.youtube.com/embed/VsG2t-rKUmA" frameborder="0" allowfullscreen></iframe> <iframe id="cKOFUZFPYp8_Youtube_api" style="width:100%;height:100%;top:0;left:0;position:absolute" frameborder="0" allowfullscreen="1" title="YouTube video player" width="640" height="360" src="https://www.youtube.com/embed/cKOFUZFPYp8?controls=0&amp;modestbranding=1&amp;rel=0&amp;showinfo=0&amp;loop=0&amp;fs=0&amp;hl=en&amp;enablejsapi=1&amp;origin=http%3A%2F%2Fspiritualtv.org&amp;widgetid=1"></iframe> """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"<video id=\"$3\" class=\"video-js vjs-default-skin vjs-fluid\" controls width=\"640\" height=\"264\" data-setup='{ \"techOrder\": [\"youtube\"], \"sources\": [{ \"type\": \"video/youtube\", \"src\": \"https://www.youtube.com/watch?v=$3\"}] }'></video>"# 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