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

r"
"
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<.*?>(\d{1,2})<.*?>\s*<.*?>(.*?)<.*?>\s*<.*?>(.*?)<.*?>"; string input = @"<head><title>Popular Baby Names</title> <meta name=""dc.language"" scheme=""ISO639-2"" content=""eng""> <meta name=""dc.creator"" content=""OACT""> <meta name=""lead_content_manager"" content=""JeffK""> <meta name=""coder"" content=""JeffK""> <meta name=""dc.date.reviewed"" scheme=""ISO8601"" content=""2006-03-10""> <link rel=""stylesheet"" href=""../OACT/templatefiles/master.css"" type=""text/css"" media=""screen""> <link rel=""stylesheet"" href=""../OACT/templatefiles/print.css"" type=""text/css"" media=""print""> </head> <body bgcolor=""#ffffff"" text=""#000000"" topmargin=""1"" leftmargin=""0""> <table width=""100%"" border=""0"" cellspacing=""0"" cellpadding=""4""> <tbody> <tr> <td class=""sstop"" valign=""bottom"" align=""left"" width=""25%""> Social Security Online </td> <td valign=""bottom"" class=""titletext""> <!-- sitetitle -->Popular Baby Names </td> </tr> <tr bgcolor=""#333366""><td colspan=""2"" height=""1""></td></tr> <tr> <td class=""graystars"" width=""25%"" valign=""top""> <a href=""../OACT/babynames/"">Popular Baby Names</a></td> <td valign=""top""> <a href=""http://www.ssa.gov/""><img src=""/templateimages/tinylogo.gif"" width=""52"" height=""47"" align=""left"" alt=""SSA logo: link to Social Security home page"" border=""0""></a> <h1>Popular Names by Birth Year</h1>September 11, 2014</td> </tr> </tbody></table> <script type=""text/javascript"" src=""../OACT/babynames/chkinput.js""></script> <table width=""100%"" border=""0"" cellspacing=""0"" cellpadding=""4"" summary=""formatting""> <tr valign=""top""> <td width=""25%"" class=""greycell""> <a href=""../OACT/babynames/background.html"">Background information</a> <p><br /> &nbsp; Select another <label for=""yob"">year of birth</label>?<br /> <form name=""popnames"" method=""post"" action=""/cgi-bin/popularnames.cgi"" onSubmit=""return submitIt();""> &nbsp; <input type=""text"" name=""year"" id=""yob"" size=""4"" value=""2012""><input type=""hidden"" name=""top"" value=""25""><input type=""hidden"" name=""number"" value=""> &nbsp; <input type=""submit"" value="" Go ""></form> </td> <td><p align=""center""><table width=""$tablewidth"" border=""1"" bordercolor=""#aaabbb"" cellpadding=""2"" cellspacing=""0"" summary=""Popularity for top 25""> <caption><h2>Popularity in 2012</h2></caption> <tr align=""center"" valign=""bottom""> <th scope=""col"" width=""12%"" bgcolor=""#efefef"">Rank</th> <th scope=""col"" width=""$colwidth"" bgcolor=""#99ccff"">Male name</th> <th scope=""col"" bgcolor=""pink"" width=""41%"">Female name</th></tr> <tr align=""right""> <td>1</td> <td>Jacob</td> <td>Sophia</td> </tr> <tr align=""right""> <td>2</td> <td>Mason</td> <td>Emma</td> </tr> <tr align=""right""> <td>3</td> <td>Ethan</td> <td>Isabella</td> </tr> <tr align=""right""> <td>4</td> <td>Noah</td> <td>Olivia</td> </tr> <tr align=""right""> <td>5</td> <td>William</td> <td>Ava</td> </tr> <tr align=""right""> <td>6</td> <td>Liam</td> <td>Emily</td> </tr> <tr align=""right""> <td>7</td> <td>Michael</td> <td>Abigail</td> </tr> <tr align=""right""> <td>8</td> <td>Jayden</td> <td>Mia</td> </tr> <tr align=""right""> <td>9</td> <td>Alexander</td> <td>Madison</td> </tr> <tr align=""right""> <td>10</td> <td>Aiden</td> <td>Elizabeth</td> </tr> <tr align=""right""> <td>11</td> <td>Daniel</td> <td>Chloe</td> </tr> <tr align=""right""> <td>12</td> <td>Matthew</td> <td>Ella</td> </tr> <tr align=""right""> <td>13</td> <td>Elijah</td> <td>Avery</td> </tr> <tr align=""right""> <td>14</td> <td>James</td> <td>Addison</td> </tr> <tr align=""right""> <td>15</td> <td>Anthony</td> <td>Aubrey</td> </tr> <tr align=""right""> <td>16</td> <td>Benjamin</td> <td>Lily</td> </tr> <tr align=""right""> <td>17</td> <td>Joshua</td> <td>Natalie</td> </tr> <tr align=""right""> <td>18</td> <td>Andrew</td> <td>Sofia</td> </tr> <tr align=""right""> <td>19</td> <td>Joseph</td> <td>Charlotte</td> </tr> <tr align=""right""> <td>20</td> <td>David</td> <td>Zoey</td> </tr> <tr align=""right""> <td>21</td> <td>Jackson</td> <td>Grace</td> </tr> <tr align=""right""> <td>22</td> <td>Logan</td> <td>Hannah</td> </tr> <tr align=""right""> <td>23</td> <td>Christopher</td> <td>Amelia</td> </tr> <tr align=""right""> <td>24</td> <td>Gabriel</td> <td>Harper</td> </tr> <tr align=""right""> <td>25</td> <td>Samuel</td> <td>Lillian</td> </tr> <tr><td colspan=""3""><small>Note: Rank 1 is the most popular, rank 2 is the next most popular, and so forth. </table></p> </td></tr></table> <table class=""printhide"" width=""100%"" border=""0"" cellpadding=""1"" cellspacing=""0""> <tr bgcolor=""#333366""><td height=""1"" colspan=""2""></td></tr> <tr> <td width=""26%"" valign=""middle"">&nbsp;</td> <td valign=""top"" class=""seventypercent""> <a href=""http://www.ssa.gov/privacy.html"">Privacy Policy</a>&nbsp; | <a href=""http://www.ssa.gov/websitepolicies.htm"">Website Policies &amp; Other Important Information</a>&nbsp; | <a href=""http://www.ssa.gov/sitemap.htm"">Site Map</a></td> </tr> </table> </body></html>"; 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