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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^(?!.*@media)[\t ]*([a-zA-Z#.:*[][^{\/]*\s*){[\s\S]*?}"; string input = @"a {color: red !important;} #p1 { margin-top: 20px !important } /* Client-specific styles */ .ExternalClass, .ExternalClass p, .ExternalClass span, .ExternalClass font, .ExternalClass td, .ExternalClass div { line-height: 100%; } a {} @media query { a { display:none } } a { display:none } } /* Media query for mobile viewport #asset_container * Developer: hero graphics should be 2 x width for HD rendering. */ @media only screen and (max-width: 480px){ table[class=max-width-pad] { max-width: 100% !important; width: 100% !important; padding-top: 15px !important; height: auto !important; } #asset_container table[class=max-width]{ max-width: 100% !important; width: 100% !important; height: auto !important; } #asset_container table[class=container]{ margin: 0 auto !important; } #asset_container .desktop-masthead{ display: none !important; } #asset_container *[class].hidden. *[class=desktop-masthead]{ display: none !important; } #asset_container *[class].elastic{ width: 100% !important; height: auto !important; } #asset_container *[class].centered{ text-align: center !important; } #asset_container *[class].fluid, #asset_container [class=fluid-mob]{ width: 100% !important; } [class=fluid-mob] { #asset_container position: relative; } .mobile-show{ display: table-cell !important; width: auto !important; height: auto !important; max-height: none !important; overflow: visible !important; visibility: visible !important; position: relative !important; text-align: center !important; } #asset_container .show-mob{ display: block !important; max-height: none !important; width: auto !important; visibility: visible !important; } #asset_container *[class].mob-masthead{ width: 100% !important; display: block !important; height: auto !important; max-height: none !important; padding: 0 !important; } #asset_container *[class].mob-masthead-img{ position: absolute !important; top: 0px !important; display: block !important; height: auto !important; max-height: none !important; padding: 0 !important; width: auto !important; } [class=fluid-mob] { display: table-cell !important; width: auto !important; height: auto !important; max-height: none !important; overflow: visible !important; visibility: visible !important; position: relative !important; text-align: center !important; } } "; RegexOptions options = RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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