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

/
/
gmi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<a\b[^>]*href\s*=\s*""cid[^""]*""[^>]*>.*<\/a>"; string substitution = @""; string input = @"<html> <head> <meta http-equiv=""Content-Type"" content=""text/html; charset=utf-8""> <meta name=""Generator"" content=""Microsoft Exchange Server""> <!-- converted from rtf --> <style><!-- .EmailQuote { margin-left: 1pt; padding-left: 4pt; border-left: #800000 2px solid; } --></style> </head> <body> <font face=""Arial"" size=""2""><span style=""font-size:10pt;""> <div>notes</div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;""><img src=""cid:0DF540471453B832E300400FF03B0900CFEC1201@1""> <a href=""cid:74D8EEA6180AD131B48DC59373FABBABD7E361BB@1"">GoodGEMSinstall.docx</a> </span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;"">&nbsp;</span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;""><b>some</b> <span style=""background-color:yellow;"">formatted</span> <font size=""6"" color=""red""><span style=""font-size:22pt;"">text</span></font></span></font></div> <div><font face=""Calibri"" size=""2"" color=""red""><span style=""font-size:11pt;"">&nbsp;</span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;""><a href=""cid:A559E9B55081418F53A3B0914D29351714C64825@1"">PowerShell_transcript.20140506143510.txt</a> </span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;"">&nbsp;</span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;""><a href=""http://www.google.com""><font color=""blue""><u>www.google.com</u></font></a></span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;"">&nbsp;</span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;"">some links <a href=""http://www.test.fr""><font color=""blue""><u>www.test.fr</u></font></a> </span></font></div> <div><font face=""Calibri"" size=""2""><span style=""font-size:11pt;"">&nbsp;</span></font></div> </span></font> </body> </html> "; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase; Regex regex = new Regex(pattern, options); 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