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

/
/
gmi

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^(?:ftp|https?):\/\/(?!$|0\.0\.0\.0)(?:(?:(?:1?\d\d?|2[0-4]\d|25[0-5])(?:\.(?!$))?){4}|(?:[a-z\d]\.|[a-z\d](?:(?![-.]{2})[a-z\d-]){0,63}?[a-z\d]\.){1,63}?[a-z]{2,63})(?:[:/].*?)?$"; string input = @"---- GOOD ---- http://10.25.41.81:6000/api/File/GetContentResult?ObjectId=62ab059f5045ea0bb69e00d9 http://10.25.41.81:6600/api/File/GetContentResult?ObjectId=62ab0d9e5045ea0bb69e00e4 http://10.25.41.81:6600/api/File/GetContentResult?ObjectId=62a89a8c4f3326cc410c40ef http://10.25.41.33:6600/api/File/GetContentResult?ObjectId=62ab04855045ea0bb69e00d7 https://websitebuilders.com https://www.fceboo.k.com/Learn-the-Net-330002341216/ ftp://aeneas.m.it.edu/ https://en.wkip.ed-i.org/wiki/Internet#Terminolog http://foo.com/blah_blah http://foo.com/blah_blah/ http://foo.com/blah_blah_(wikipedia) http://foo.com/blah_blah_(wikipedia)_(again) http://www.example.com/wpstyle/?p=364 https://www.example.com/foo/?bar=baz&inga=42&quux http://a.ws/䨹 http://foo.com/blah_(wikipedia)#cite-1 http://foo.com/blah_(wikipedia)_blah#cite-1 http://foo.com/unicode_(✪)_in_parens http://foo.com/(something)?after=parens http://code.google.com/events/#&product=browser http://js.mp ftp://foo.bar/baz http://foo.bar/?q=Test%20URL-encoded%20stuff http://1337.net http://a.b-c.de http://223.255.255.254 https://example.com/././foo https://EXAMPLE.com/../x https://example.org// https://example.org/foo bar http://foo.bar/foo(bar)baz quux https://example.com:demo https://r.com/r/zxVH ---- BAD ---- https://user:password@example.org/ http://userid:password@example.com:8080 http://userid:password@example.com:8080/ http://userid:password@example.com http://userid:password@example.com/ http://userid@example.com http://userid@example.com/ http://userid@example.com:8080 http://userid@example.com:8080/ file://loc%61lhost/ http://⌘.ws http://⌘.ws/ http://☺.damowmow.com/ http://✪df.ws/123 http://[www.example.com]/ https://ex ample.org/ file://C|/demo \example\..\demo/.\ https:example.org https://////example.com/// http://0.0.0.0 http://3628126748 http://www.foo.bar./ http://a.b-.co http://-a.b.co http://-error-.invalid/ http://~_!$&'()*+,;=:%40:80%2f::::::@example.com http:// http://. http://.. http://../ http://? http://?? http://??/ http://# http://## http://##/ http://foo.bar?q=Spaces should be encoded // //a ///a /// http:///a foo.com rdar://1234 h://test http:// shouldfail.com :// should fail ftps://foo.bar/ http://.www.foo.bar/ http://.www.foo.bar./ "; RegexOptions options = RegexOptions.Multiline | 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