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

/
/
gi

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<td><a href=""(http:\/\/adi.sunyconnect.suny.edu:4610\/F\/\?request=\d{6,6}&func=find-b&find_code=sys&local_base=adi01pub)"">(.*?)<b><br>(.*?) \/ (.*?)<\/b>"; string input = @"<html> <head> <meta http-equiv=""Content-Type"" content=""text/html; charset=utf-8"" /> <meta http-equiv=""Content-Language"" content=""en-us"" /> <link rel=""stylesheet"" type=""text/css"" href=""/app/exlibris/sny_scripts/new_items_list/new_items.css"" /> <title>Adirondack Community College Library - New Titles List</title> <script type=""text/javascript"" src=""http://www.sunyconnect.suny.edu/gbs_cover_art/gbs_covers.js""></script> </head> <body> <a name=""top""></a> <table width=""90%"" align=""center"" border=""0"" cellpadding=""0"" cellspacing=""0""> <table id=""Table_01"" width=""100%"" height=""48"" border=""0"" cellpadding=""0"" cellspacing=""0""> <tr> <td> <table width=""100%"" border=""0"" cellspacing=""0"" cellpadding=""0"" align=""center""> <tr bgcolor=""#006500""> <td class=""topbar"" valign=""bottom"" align=""right""> <a href=""http://www.sunyacc.edu/go.php?page=academics/library.html"" class=""blue"" target=new title=""link to the library home page""> <img src=""http://adi.sunyconnect.suny.edu:4610/aleph/prod/adi/alephe/www_f_eng/icon/logo.gif"" border=""0"" alt=""Library Logo"" align=""left""></a> </td> <!-- <td class=""topbar"" valign=""middle"" align=""center""> </td> --> </tr> </table> <center><h2> Adirondack Community College Library<br> New Titles List </h2></center> <p> <center> <font color=""#006500""><b><i> This list shows the most recent additions to the library collection. Items are in call number order. <br> Click on the title to get to the full catalog record.</i></b></font> </center> </td></tr></table> <!-- Close table opened in header_2 --> </table> <table align=""center"" cellspacing=""20""> <tr><td> <a href=""#A"">A - General Works, Encyclopedias, Dictionaries<br> <a href=""#B"">B - Philosophy, Psychology, Religion<br> <a href=""#C"">C - History of Civilization, Archeology, Chronologies,<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Genealogy, Biography<br> <a href=""#D"">D - History: General and World History<br> <a href=""#E"">E - History: America<br> <a href=""#F"">F - History: America - Regional, State<br> <a href=""#G"">G - Geography, Environmental Sciences, Anthropology,<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Folklore, Recreation, Sports<br> <a href=""#H"">H - Social Sciences<br> <a href=""#J"">J - Political Science<br> <a href=""#K"">K - Law<br> </td><td> <a href=""#L"">L - Education <br> <a href=""#M"">M - Music, books about Music<br> <a href=""#N"">N - Fine Arts<br> <a href=""#P"">P - Language and Literature<br> <a href=""#Q"">Q - Science<br> <a href=""#R"">R - Medicine, Nursing, Pharmacology, Psychiatry<br> <a href=""#S"">S - Agriculture<br> <a href=""#T"">T - Technology, Engineering, Aeronautics,<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Photography, Handicrafts<br> <a href=""#U"">U - Military Science<br> <a href=""#V"">V - Naval Science<br> <a href=""#Z"">Z - Library Science, Bibliography<br> </td></tr> </table> <table width=""75%"" align=""center"" border=""0"" cellpadding=""0"" cellspacing=""0""><tr><td> <h4>LC Call Number:</h4> <font color=""#000000"" size=""1""><a href=""http://www.loc.gov/catdir/cpso/lcco/lcco.html"" target=""_new""> Guide to LC Classification</a> - (click for more information on the call letters for a subject) </font></p> [<b><a HREF=""#A"">A</a></b>] [<b><a HREF=""#B"">B</a></b>] [<b><a HREF=""#C"">C</a></b>] [<b><a HREF=""#D"">D</a></b>] [<b><a HREF=""#E"">E</a></b>] [<b><a HREF=""#F"">F</a></b>] [<b><a HREF=""#G"">G</a></b>] [<b><a HREF=""#H"">H</a></b>] [<b><a HREF=""#J"">J</a></b>] [<b><a HREF=""#K"">K</a></b>] [<b><a HREF=""#L"">L</a></b>] [<b><a HREF=""#M"">M</a></b>] [<b><a HREF=""#N"">N</a></b>] [<b><a HREF=""#P"">P</a></b>] [<b><a HREF=""#Q"">Q</a></b>] [<b><a HREF=""#R"">R</a></b>] [<b><a HREF=""#S"">S</a></b>] [<b><a HREF=""#T"">T</a></b>] [<b><a HREF=""#U"">U</a></b>] [<b><a HREF=""#V"">V</a></b>] [<b><a HREF=""#Z"">Z</a></b>] <br> </td></tr></table> <table width=80%><tr><td>&nbsp;</td></tr><tr><td align=right> <font size=1>Last updated: Mon 01-25-2016</font> </td></tr></table> <table width=90% align=center border=0 cellpadding=0 cellspacing=0> <tr><td> <A NAME=""A""> </A><b><font size=+3>A</font></b></a></td><td>&nbsp; </td></tr> <tr><td> <A NAME=""B""> </A><b><font size=+3>B</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233654&func=find-b&find_code=sys&local_base=adi01pub"">BX1751.3 .C377 2015 Adirondack Community College Circulating<b><br>The Catholic Church / Michael Ruth, book editor.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""C""> </A><b><font size=+3>C</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""D""> </A><b><font size=+3>D</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233656&func=find-b&find_code=sys&local_base=adi01pub"">DK508.852 .U39 2016 Adirondack Community College Circulating<b><br>Ukraine / Michael Ruth, book editor.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""E""> </A><b><font size=+3>E</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""F""> </A><b><font size=+3>F</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""G""> </A><b><font size=+3>G</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""H""> </A><b><font size=+3>H</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233657&func=find-b&find_code=sys&local_base=adi01pub"">HC110.I5 I477 2016 Adirondack Community College Circulating<b><br>Income inequality / Noël Merino, Book Editor.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233652&func=find-b&find_code=sys&local_base=adi01pub"">HQ766 .B4794 2016 Adirondack Community College Circulating<b><br>Birth control / Jack Lasky, book editor.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233655&func=find-b&find_code=sys&local_base=adi01pub"">HV9471 .A49 2016 Adirondack Community College Circulating<b><br>America's prisons / Jack Lasky, book editor.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""J""> </A><b><font size=+3>J</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""K""> </A><b><font size=+3>K</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""L""> </A><b><font size=+3>L</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""M""> </A><b><font size=+3>M</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""N""> </A><b><font size=+3>N</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""P""> </A><b><font size=+3>P</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233650&func=find-b&find_code=sys&local_base=adi01pub"">PC2129.E5 R59 2009 Adirondack Community College Circulating<b><br>Easy French step-by-step : master high-frequency grammar for French proficiency--fast! / Myrna Bell</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233648&func=find-b&find_code=sys&local_base=adi01pub"">PF3271 .H39 2011 Adirondack Community College Circulating<b><br>German verb drills / Astrid Henschel.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233658&func=find-b&find_code=sys&local_base=adi01pub"">PN1997.2 .I54 2015 Adirondack Community College DVD<b><br>Infinitely polar bear / a Sony Pictures Classics release ; Paper Street Films and Park Pictures pres</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233649&func=find-b&find_code=sys&local_base=adi01pub"">PR830.W6 P45 2014 Adirondack Community College Circulating<b><br>Women's fiction : from 1945 to today / Deborah Philips.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""Q""> </A><b><font size=+3>Q</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""R""> </A><b><font size=+3>R</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233647&func=find-b&find_code=sys&local_base=adi01pub"">RB115 .B823 2016 Adirondack Community College Reference<b><br>2016 ICD-10-CM for physicians professional edition / Carol J. Buck.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""S""> </A><b><font size=+3>S</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233651&func=find-b&find_code=sys&local_base=adi01pub"">S596.7 .V57 2015 Adirondack Community College Circulating<b><br>Visual soil evaluation : realizing potential crop production with minimum environmental impact / edi</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""T""> </A><b><font size=+3>T</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td>&nbsp;</td><td><a href=""http://adi.sunyconnect.suny.edu:4610/F/?request=233653&func=find-b&find_code=sys&local_base=adi01pub"">TK5105.8855 .I58 2016 Adirondack Community College Circulating<b><br>The Internet / Jack Lasky, Book Editor.</b></a></td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""U""> </A><b><font size=+3>U</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""V""> </A><b><font size=+3>V</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> <tr><td> <A NAME=""Z""> </A><b><font size=+3>Z</font></b></td><td><a HREF=""#top"">Back to top</a> </td></tr><tr><td>&nbsp;</td></tr> </table> </body> </html> "; RegexOptions options = RegexOptions.IgnoreCase; 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