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

@
@
gmis

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<a[^>]*href=""(?<url>[^""]*(?<=\?|&)o=(?<number>\d+)[^""]*)""[^>]*>\s*last"; string input = @"<div class=""listing_thumbs_resultcontainer""> <span class=""FloatLeft nav-next-btn""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&amp;q=nike air&amp;th=1"" title=""Go to first page"">« First</a> <span class=""nav-next-btn nohistory marginLeft""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&amp;q=nike air&amp;th=1"" title=""Go to previous page""> ‹ Previous </a> </span> &nbsp; <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&amp;q=nike air&amp;th=1"" title=""Page 1 of 29"">1</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=2&amp;q=nike air&amp;th=1"" title=""Page 2 of 29"">2</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=3&amp;q=nike air&amp;th=1"" title=""Page 3 of 29"">3</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=4&amp;q=nike air&amp;th=1"" title=""Page 4 of 29"">4</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=5&amp;q=nike air&amp;th=1"" title=""Page 5 of 29"">5</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=6&amp;q=nike air&amp;th=1"" title=""Page 6 of 29"">6</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=7&amp;q=nike air&amp;th=1"" title=""Page 7 of 29"">7</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=8&amp;q=nike air&amp;th=1"" title=""Page 8 of 29"">8</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=9&amp;q=nike air&amp;th=1"" title=""Page 9 of 29"">9</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=10&amp;q=nike air&amp;th=1"" title=""Page 10 of 29"">10</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=11&amp;q=nike air&amp;th=1"" title=""Page 11 of 29"">11</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=12&amp;q=nike air&amp;th=1"" title=""Page 12 of 29"">12</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=13&amp;q=nike air&amp;th=1"" title=""Page 13 of 29"">13</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=14&amp;q=nike air&amp;th=1"" title=""Page 14 of 29"">14</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=15&amp;q=nike air&amp;th=1"" title=""Page 15 of 29"">15</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=16&amp;q=nike air&amp;th=1"" title=""Page 16 of 29"">16</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=17&amp;q=nike air&amp;th=1"" title=""Page 17 of 29"">17</a> </span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&amp;q=nike air&amp;th=1"" title=""Page 18 of 29"">18</a> </span> <span class=""nav-active""><strong>19</strong></span> <span class=""non-active nohistory""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&amp;q=nike air&amp;th=1"" title=""Page 20 of 29"">20</a> </span </span> <span class=""nav-next-btn nohistory FloatRight""> <span class=""nav-next-btn nohistory marginRight""> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&amp;q=nike air&amp;th=1"" title=""Go to next page""> Next › </a> </span> <a href=""http://www.mudah.my/Malaysia/nike+air-for-sale?o=29&amp;q=nike air&amp;th=1"" title=""Go to last page""> Last » </a> </span> </div>"; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase | RegexOptions.Singleline; 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