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

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?<AttributeName>(?:src|background))\s*=\s*[""'](?<AttributeValue>(?:[^""'])*)"; string input = @"<html> <table id='tblTest' border=""1""> <tr> <td colspan=""1"" >CellA</td> </tr> <tr> <td>Click<a href=""http://mail.google.com"" >here</a></td> </tr> <tr> <td> <img src=""http://wcrustine.org/Portals/0/click_here_button.jpg"" style=""width:100px;height:100px;""></img></td> </tr> <tr> <td background=""https://ci6.googleuser.com/proxy/d-NpaBfbly5hKSic8pomfvI4scwJqkF2wwmRqEB4stR8jfO7jo-Sx-JcVLfIXqw5gJnd05Rl0aY3evT2DhmS6he85ifLGQA=s0-d-e1-ft#http://newsletter.mydomain.com/template/header_bg.jpg"" bgcolor=""#336699"" height=""100"" style=""background:url(https://ci5.googleuser.com/proxy/d-NpaBfbly5hKSic8pomfvI4scwJqkF2wwmRqEB4stR8jJrvfO7jo-Sx-JcVLfIgJnd05Rl0aY3evT2DhmS6LU85ifLGQA=s0-d-e1-ft#http://newsletter.mydomain.com/template/header_bg.jpg) top left repeat #336699"" width=""> &nbsp; </td> </tr> </table> </html>"; foreach (Match m in Regex.Matches(input, pattern)) { 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