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 = @"(?i)(?<="")\s*(?:https?)?:\/\/[^""]+\/(?=[^""]*logo)[^""]*(?:png|jpe?g|gif|tiff)\s*(?="")"; string input = @"<link rel=""icon"" href=""https://diabsolut.com/wp-content/uploads/2018/02/D-Logo-150x150.png"" sizes=""32x32""> <link rel=""icon"" href=""https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png"" sizes=""192x192""> <link rel=""apple-touch-icon-precomposed"" href=""https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png""> <meta name=""msapplication-TileImage"" content=""https://diabsolut.com/wp-content/uploads/2018/02/D-Logo.png""> <img width=""200"" height=""147"" src=""https://diabsolut.com/wp-content/uploads/2017/05/Diabsolut-logo-01-e1496083111444.png"" class=""attachment-large size-large"" alt=""> <img src=""https://diabsolut.com/wp-content/uploads/2019/03/White-FSM-logo.png"" width=""330"" height=""215"" data-no-retina="" style=""> <img src=""https://diabsolut.com/wp-content/uploads/2017/05/Diabsolut-Cloud-Logo-Web-1.png"" width=""277"" height=""81"" data-no-retina="" style=""height: 100%; width: 100%; text-align: left; line-height: 16px; letter-spacing: 0px; font-weight: 300; font-size: 12px; border-color: rgb(255, 255, 255); border-style: none; margin: 0px; border-radius: 0px; padding: 0px;"" data-stylerecorder=""true""> <img width=""300"" height=""179"" src=""https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo-300x179.png"" class=""attachment-medium size-medium"" alt="" srcset=""https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo-300x179.png 300w, https://diabsolut.com/wp-content/uploads/2017/05/Watershed-CI-Logo.png 350w"" sizes=""(max-width: 300px) 100vw, 300px""></a></div><h4 style=""text-align: center"" class=""vc_custom_heading vc_custom_1508180231294"">Consulting Solutions</h4> logout"; 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