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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
img

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @/ ^(.*\/thumb\/[0-9a-f]\/[0-9a-f]{2}\/)([^\/]+\.(jpg|jpeg|png|gif))\/\d+px-(\2) /; string input = @"https://upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Royal_tyrrell_entrance.JPG/800px-Royal_tyrrell_entrance.JPG https://upload.wikimedia.org/wikipedia/commons/6/6d/Royal_tyrrell_entrance.JPG https://upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Royal_tyrrell_entrance.jpg/800px-Royal_tyrrell_entrance.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Royal_tyrrell_entrance.jpeg/800px-Royal_tyrrell_entrance.jpeg https://upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Royal_tyrrell_entrance.png/800px-Royal_tyrrell_entrance.png https://upload.wikimedia.org/wikipedia/commons/thumb/6/6d/Royal_tyrrell_entrance.gif/800px-Royal_tyrrell_entrance.gif //upload.wikimedia.org/wikipedia/commons/thumb/c/cf/Flag_of_Canada.svg/30px-Flag_of_Canada.svg.png 1.5x <img alt="" src=""//upload.wikimedia.org/wikipedia/commons/thumb/8/8e/Royal_Tyrrell_Museum.JPG/220px-Royal_Tyrrell_Museum.JPG"" decoding=""async"" width=""220"" height=""165"" srcset=""//upload.wikimedia.org/wikipedia/commons/thumb/8/8e/Royal_Tyrrell_Museum.JPG/330px-Royal_Tyrrell_Museum.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8e/Royal_Tyrrell_Museum.JPG/440px-Royal_Tyrrell_Museum.JPG 2x"" data-file-width=""4000"" data-file-height=""3000""> <img alt="" src=""//upload.wikimedia.org/wikipedia/commons/thumb/9/91/Joseph_Burr_Tyrrell_bust.jpg/220px-Joseph_Burr_Tyrrell_bust.jpg"" decoding=""async"" width=""220"" height=""293"" srcset=""//upload.wikimedia.org/wikipedia/commons/thumb/9/91/Joseph_Burr_Tyrrell_bust.jpg/330px-Joseph_Burr_Tyrrell_bust.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/91/Joseph_Burr_Tyrrell_bust.jpg/440px-Joseph_Burr_Tyrrell_bust.jpg 2x"" data-file-width=""1536"" data-file-height=""2048""> "; RegexOptions options = RegexOptions.IgnoreCase | 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