Regular Expressions 101

Save & Share

  • Regex Version: ver. 40
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?<variable><variable.+?source=[\\]*""(?<source>.*?)[\\]*"".*?>.*?<\/variable>)"; string input = @"customtracking=\""[{&quot;name&quot;:&quot;utm_source&quot;,&quot;value&quot;:&quot;Loopify&quot;},{&quot;name&quot;:&quot;utm_campaign&quot;,&quot;value&quot;:&quot;​​&quot;},{&quot;name&quot;:&quot;utm_medium&quot;,&quot;value&quot;:&quot;Page&quot;},{&quot;name&quot;:&quot;utm_content&quot;,&quot;value&quot;:&quot;​<variable contenteditable=\\&quot;false\\&quot; name=\\&quot;link type\\&quot; source=\\&quot;campaign.linkType\\&quot; placeholder=\\&quot;\\&quot; date-locale=\\&quot;\\&quot; date-format=\\&quot;\\&quot;>link type</variable>​&quot;}]\"" class=\""loopify-link\"">aliquam</a>, lobortis ante eu, consectetur nulla. Sed vitae posuere purus. Vivamus pretium et ipsum vel pretium. Nunc elementum tempus magna id iaculis."",""button1"":""Google"",""button2"":""Read more""},""link1"":{""type"":""website"",""url"":""https://www.google.com"",""uuid"":""1a61717c-a686-4683-450c-5fa775b74b6f"",""target"":""_blank"",""title"":"",""customTracking"":[{""name"":""utm_source"",""value"":""Loopify""},{""name"":""utm_campaign"",""value"":""​<variable contenteditable=\""false\"" name=\""campaign name\"" source=\""campaign.campaignName\"" placeholder=\""\"" date-locale=\""\"" date-format=\""\"">campaign name</variable>​""},{""name"":""utm_medium"",""value"":""Page""},{""name"":""utm_content"",""value"":""​<variable contenteditable=\""false\"" name=\""link type\"" source=\""campaign.linkType\"" placeholder=\""\"" date-locale=\""\"" date-format=\""\"">link type</variable>​""}]}"; foreach (Match m in Regex.Matches(input, pattern)) { 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