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

/
/
ig

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\b((https?|ftps?):\/\/[^""<\s]+)(?![^<>]*>|[^""]*?<\/a)"; string input = @"""http://www.website.com"" https://www.website.com ""ftp://www.website.com ftps://www.website.com <u>http://www.website.com</u> This is a link http://www.website.com that is not linked ftp://www.website.com This is a long link http://www.website.com/index.htm?foo=bar <a href=""http://www.website.com"" target=""_blank"">http://website.com</a > <a href=""https://www.website.com"">http://website.com</a> <a href=""http://www.website.com""><u>http://www.website.com</u></a> <a href=""ftp://www.website.com"">ftp://www.website.com</a> <img src=""http://www.website.com"" target=""_blank""/> <a href=""http://www.website.com"" target=""_blank""> http://website.com </a> <a href=""http://www.website.com""> http://www.website.com http://www.website.com </a> Lorem ipsum Test dolor sit amet, consetetur sadhttp://url.comipscing elitr, sed diam <a href=""http://Test.com/url"">Test</a> eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam http://url.com et justo... <a href=""http://www.website.com""> http://www.website.com <img src=""http://www.website.com"" target=""_blank""/> http://www.website.com </a>"; 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