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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(<label(?!.*preferredMaxLayoutWidth).*numberOfLines.*>)"; string substitution = @""; string input = @" <label opaque=""NO"" userInteractionEnabled=""NO"" tag=""5"" contentMode=""left"" horizontalHuggingPriority=""251"" verticalHuggingPriority=""251"" text=""Label"" lineBreakMode=""tailTruncation""=""4"" baselineAdjustment=""alignBaselines"" adjustsFontSizeToFit=""NO"" translatesAutoresizingMaskIntoConstraints=""NO"" id=""fgY-Rp-veR""> <rect key=""frame"" x=""6"" y=""40"" width=""288"" height=""60""/> <animations/> <constraints> <constraint firstAttribute=""height"" constant=""60"" id=""g3c-hD-Hf9""/> </constraints> <fontDescription key=""fontDescription"" type=""system"" pointSize=""12""/> <color key=""textColor"" red=""0.0"" green=""0.0"" blue=""0.0"" alpha=""1"" colorSpace=""calibratedRGB""/> <nil key=""highlightedColor""/> </label> <label opaque=""NO"" userInteractionEnabled=""NO"" numberOfLines=""4"" tag=""10"" contentMode=""left"" text=""feedback"" lineBreakMode=""tailTruncation"" numberOfLines=""4"" baselineAdjustment=""alignBaselines"" adjustsFontSizeToFit=""NO"" translatesAutoresizingMaskIntoConstraints=""NO"" id=""M98-QE-PMx""> <rect key=""frame"" x=""7"" y=""227"" width=""287"" height=""70""/> <animations/> <constraints> <constraint firstAttribute=""height"" constant=""70"" id=""uPb-iM-7XM""/> </constraints> <fontDescription key=""fontDescription"" type=""system"" pointSize=""14""/> <color key=""textColor"" red=""0.058823529409999999"" green=""0.51372549020000002"" blue=""0.94901960780000005"" alpha=""1"" colorSpace=""calibratedRGB""/> <nil key=""highlightedColor""/> </label>"; Regex regex = new Regex(pattern); string result = regex.Replace(input, substitution); } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx