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

/
/
msi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?smi)^.*tag="[A-Z]_([A-Z]{2})_(\d{4}).*$"# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive, .dotMatchesLineSeparators]) let testString = ##""" <?xml version="1.0"?> -<PEGraphic gridSpaceY="100" gridSpaceX="100" bkgdImage="" gridColor="#333333" paperColor="#000000" width="19600" height="14200" version="5"> <Font height="120" name="Arial"/> -<Polyline backFill="yes" backColor="#FFFFFF"> <Location right="6020" bottom="12445" left="6018" top="11741"/> <Pen width="2" style="solid" color="#00FF00"/> <Brush style="hollow" color="#00FF00"/> <Point y="11741" x="6019"/> <Point y="12445" x="6019"/> </Polyline> -<Polyline backFill="yes" backColor="#E0E0E0"> <Location right="3365" bottom="12835" left="3363" top="11741"/> <Pen width="2" style="solid" color="#00FF00"/> <Brush style="hollow" color="#00FF00"/> <Point y="11741" x="3364"/> <Point y="12835" x="3364"/> </Polyline> -<Polyline backFill="yes" backColor="#FFFFFF"> <Location right="4627" bottom="6800" left="4521" top="5100"/> <Pen width="2" style="solid" color="#00FF00"/> <Brush style="hollow" color="#00FF00"/> <Datasource stepped="no" server="USFRPVMESPOLYOL" map="IP_DIMAP" field="VAL" tag="p_dc_1730"/> -<Animation on="yes"> <AnimationRange color="#666666" image="" text="act sp" max="0" min="0" index="1"/> <AnimationRange color="#00FF00" image="" text="act sp" max="1" min="1" index="2"/> </Animation> <Point y="5100" x="4627"/> <Point y="6800" x="4627"/> </Polyline> -<Polyline backFill="yes" backColor="#FFFFFF"> <Location right="3719" bottom="4394" left="1918" top="3300"/> <Pen width="2" style="solid" color="#00FF00"/> <Brush style="hollow" color="#00FF00"/> <Datasource stepped="no" server="USFRPVMESPOLYOL" map="" field="VAL" tag="P_DC_2103"/> -<Animation on="yes"> <AnimationRange color="#666666" image="" text="act sp" max="0" min="0" index="1"/> <AnimationRange color="#00FF00" image="" text="act sp" max="1" min="1" index="2"/> </Animation> <Point y="4394" x="3718"/> <Point y="4098" x="3718"/> <Point y="4098" x="1918"/> <Point y="3300" x="1918"/> </Polyline> """## let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"CG $1($2)"# let lookupRange = (testString as NSString).range(of: pattern, options: .regularExpression, range: stringRange) if lookupRange.intersection(stringRange) != nil { let result = regex.stringByReplacingMatches(in: testString, range: lookupRange, withTemplate: substitutionString) print(result) } else { print("No matches were found.") }

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