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
Processing...

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<a (.*?)test(.*?)<\/a>"; string input = @"<a style=""text-decoration: none;"" target=""_blank"" href=""http://example.com/?qs=df8fc6df1b3b6e7b87c5c8da8e2c0ad34b73a19751c15d1b3efbf37c3ded58b9cca09ee6d80e64bc""><img width=""120"" height=""81"" border=""0"" style=""display: block; font-family: Arial,Helvetica,sans-serif; font-size: 14px; color: #004990;"" title=""example.com"" alt=""example.com"" src=""http://example.com/lib/fe8f12717d67017f72/m/5/20140513_example_Logo1.jpg"" /></a></td> </tr> <tr> <td valign=""top"" align=""left""> <table width=""100%"" cellspacing=""0"" cellpadding=""0"" border=""0""> <tbody> <tr> <td valign=""top"" height=""17"" align=""left"" style=""font-size: 0%;""><img width=""1"" height=""17"" border=""0"" style=""display: block;"" title="" alt="" src=""http://example.com/lib/fe8f12717d62057f7d/m/1/img_spacer.gif"" /></td> </tr> <tr> <td valign=""top"" align=""left"" style=""font-family: Arial,Helvetica,sans-serif; font-size: 11px; color: #656c73; line-height: 18px;"">You are subscribed as <a reportname=""mailto:_EMAIL__"" style=""text-decoration: none; color: #505050;"" href=""example@example.com""><span class=""link3"" style=""text-decoration: none;"">example@example.com</span></a></td> </tr> <tr> <td valign=""top"" height=""25"" align=""left"" style=""font-size: 0%;""><img width=""1"" height=""25"" border=""0"" style=""display: block;"" title="" alt="" src=""http://example.com"" /></td> </tr> <tr> <td valign=""top"" align=""left"" style=""font-family: Arial,Helvetica,sans-serif; font-size: 11px; color: #656c73; line-height: 18px;"">View and manage your <span class=""applefooterlinks"">example.com </span><a style=""text-decoration: underline; color: #656c73;"" target=""_blank"" href=""http://example.com/""><span class=""link3"" style=""color: #656c73; text-decoration: underline;"">newsletter preferences</span></a>.<br /> If you wish to unsubscribe you must uncheck the box next to the relevant title.</td> </tr> <tr> <td valign=""top"" height=""25"" align=""left"" style=""font-size: 0%;""><img width=""1"" height=""25"" border=""0"" style=""display: block;"" title="" alt="" src=""http://example.com"" /></td> </tr> <tr> <td valign=""top"" align=""left"" style=""font-family: Arial,Helvetica,sans-serif; font-size: 11px; color: #656c73; line-height: 18px;""><a style=""text-decoration: underline; color: #656c73;"" target=""_blank"" href=""http://example.com/?qs=85ea4dcfb406c17e184090f0720216d008d21d0363ca86741a296ce98649846e5262048f59eea25e""><span class=""link3"" style=""color: #656c73; text-decoration: underline;"">TEST</span></a>"; RegexOptions options = RegexOptions.IgnoreCase | RegexOptions.Multiline; Match m = Regex.Match(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