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

/
/
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<(\w+)(?: +(\w+)=""[\w,;.:\-#'+~*?=&%\$!\/'\]\[@\(\)\s]*"")*"; string input = @"<p><li first=""1"" second=""2"" third=""3""></li><b><br/><p><li first=""1"" second=""2"" third=""3""></li><b><br/></p> <p><li first=""1"" second=""2""></li><b><br/><p><li first=""1"" second=""2""></li><b><br/></p> <p><li first=""1""></li><b><br/><p><li first=""1""></li><b><br/></p> <p><a href=""http://www.quackit.com/html/tutorial/html_links.cfm"">Example Link</a></p> <div class=""more-info""><a href=""http://www.quackit.com/html/examples/html_links_examples.cfm"">More Link Examples...</a></div> <li style=""-moz-float-edge: content-box"">... that <a href=""/wiki/Orval_Overall"" title=""Orval Overall"">Orval Overall</a> <i>(pictured)</i> is the only <b><a href=""/wiki/List_of_Major_League_Baseball_pitchers_who_have_struck_out_four_batters_in_one_inning"" title=""List of Major League Baseball pitchers who have struck out four batters in one inning"">Major League Baseball player to strike out four batters in one inning</a></b> in the <a href=""/wiki/World_Series"" title=""World Series"">World Series</a>?</li> <li style=""-moz-float-edge: content-box"">... that the three cities of the <b><a href=""/wiki/West_Triangle_Economic_Zone"" title=""West Triangle Economic Zone"">West Triangle Economic Zone</a></b> contribute 40% of Western China's GDP?</li> <li style=""-moz-float-edge: content-box"">... that <i><a href=""/wiki/Kismet_(1943_film)"" title=""Kismet (1943 film)"">Kismet</a></i>, directed by <b><a href=""/wiki/Gyan_Mukherjee"" title=""Gyan Mukherjee"">Gyan Mukherjee</a></b>, ran at the <a href=""/wiki/Roxy_Cinema_(Kolkata)"" title=""Roxy Cinema (Kolkata)"">Roxy, Kolkata</a>, for 3 years and 8 months?</li> <li style=""-moz-float-edge: content-box"">... that <a href=""/wiki/Vauix_Carter"" title=""Vauix Carter"">Vauix Carter</a> both coached and played for the <b><a href=""/wiki/1882_Navy_Midshipmen_football_team"" title=""1882 Navy Midshipmen football team"">1882 Navy Midshipmen football team</a></b>?</li> <li style=""-moz-float-edge: content-box"">... that <a href=""/wiki/Zhu_Chenhao"" title=""Zhu Chenhao"">Zhu Chenhao</a> was sentenced to <a href=""/wiki/Slow_slicing"" title=""Slow slicing"">slow slicing</a> for leading the <b><a href=""/wiki/Prince_of_Ning_rebellion"" title=""Prince of Ning rebellion"">Prince of Ning rebellion</a></b> against the <a href=""/wiki/Ming_Dynasty"" title=""Ming Dynasty"">Ming Dynasty</a> <a href=""/wiki/Zhengde_Emperor"" title=""Zhengde Emperor"">emperor Zhengde</a>?</li> <li style=""-moz-float-edge: content-box"">... that <b><a href=""/wiki/Mirza_Adeeb"" title=""Mirza Adeeb"">Mirza Adeeb</a></b> was a prominent modern Pakistani <a href=""/wiki/Urdu"" title=""Urdu"">Urdu</a> playwright whose later work focuses on social problems and daily life?</li> <li style=""-moz-float-edge: content-box"">... that in <i><b><a href=""/wiki/La%C3%9Ft_uns_sorgen,_la%C3%9Ft_uns_wachen,_BWV_213"" title=""Lat uns sorgen, lat uns wachen, BWV 213"">Die Wahl des Herkules</a></b></i>, Hercules must choose between the good cop and the bad cop?<br style=""clear:both;"" /> <div style=""text-align: right;"" class=""noprint""><b><a href=""/wiki/Wikipedia:Recent_additions"" title=""Wikipedia:Recent additions"">Archive</a></b> <b><a href=""/wiki/Wikipedia:Your_first_article"" title=""Wikipedia:Your first article"">Start a new article</a></b> <b><a href=""/wiki/Template_talk:Did_you_know"" title=""Template talk:Did you know"">Nominate an article</a></b></div> </li>"; 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