Regular Expressions 101

Save & Share

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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(https\:\\\/\\\/video2\.+)([a-zA-Z0-9]+)(\.com\\\/key\=+)([a-zA-Z0-9+-]+)(\,end\=[a-zA-Z0-9]+)(\,limit\=3\\\/data\=)([a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\-mv\\\/speed\=[a-zA-Z0-9]+)(\\\/initial\_buffer\=[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\\\/[a-zA-Z0-9]+)(\.[a-zA-Z0-9]+)(\.mp4)"; string input = @"https:\/\/thumb-v-cl2.xhcdn.com\/a\/UpUWjQ0naov6PDPQutV2gQ\/009\/977\/291\/320x240.3.jpg"",""platform"":""android"",""duration"":726,""fallback"":{""fallbackImageClass"":""xplayer-fallback-image""},""hlsConfig"":{""libSrc"":""https:\/\/static-cl.xhcdn.com\/js\/hls.js"",""maxBufferLength"":10,""maxBufferSize"":10000000,""maxMaxBufferLength"":120},""sources"":{""standard"":{""vp9"":[{""url"":""https:\/\/video5.xhcdn.com\/key=ArIS24azT212T7rlq2JYOA,end=1534017600,limit=3\/data=107.12.224.13-mv\/speed=294k\/initial_buffer=657952\/009\/977\/291\/720p.vp9.webm"",""fallback"":""https:\/\/19-14.b.cdn13.com\/009\/977\/291\/720p.vp9.webm?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=294k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=8f32053b3a204e397e1c509d8c55b8c6"",""quality"":""720p"",""label"":""720p"",""type"":""HD""}],""h265"":[{""url"":""https:\/\/video4.xhcdn.com\/key=USM0qN+ZPKuWvDQ930QxQw,end=1534017600,limit=3\/data=107.12.224.13-mv\/speed=232k\/initial_buffer=657952\/009\/977\/291\/720p.h265.mp4"",""fallback"":""https:\/\/19-13.b.cdn13.com\/009\/977\/291\/720p.h265.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=232k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=7d666c372589a913757eecc6c2dc11da"",""quality"":""720p"",""label"":""720p"",""type"":""HD""}],""mp4"":[{""url"":""https:\/\/video2.xhcdn.com\/key=BiIiv7GdsQSuPxg9SRIrbg,end=1534017600,limit=3\/data=107.12.224.13-mv\/speed=464k\/initial_buffer=657952\/009\/977\/291\/720p.h264.mp4"",""fallback"":""https:\/\/19-11.b.cdn13.com\/009\/977\/291\/720p.h264.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=464k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=7e82410ea292a37c1daaf359699d3953"",""quality"":""720p"",""label"":""720p"",""type"":""HD""},{""url"":""https:\/\/video2.xhcdn.com\/key=hpb+W+8whtZRJw+jfMdHUw,end=1534017600,limit=3\/data=107.12.224.13-mv\/speed=242k\/initial_buffer=657952\/009\/977\/291\/480p.h264.mp4"",""fallback"":""https:\/\/19-11.b.cdn13.com\/009\/977\/291\/480p.h264.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=242k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=49929359209c0d9c6cd7deb8e90ecd22"",""quality"":""480p"",""label"":""480p"",""type"":""},{""url"":""https:\/\/video2.xhcdn.com\/key=7geyd-JfggobJpYnpAdaHw,end=1534017600,limit=3\/data=107.12.224.13-mv\/speed=120k\/initial_buffer=657952\/009\/977\/291\/240p.h264.mp4"",""fallback"":""https:\/\/19-11.b.cdn13.com\/009\/977\/291\/240p.h264.mp4?cdn_creation_time=1534003200&cdn_ttl=14400&cdn_bw=120k&cdn_bw_fs=643k&cdn_cv_data=107.12.224.13-mv&cdn_hash=e251646a2b28b9802a3c6570550001bc"",""quality"":""240p"",""label"":""240p"",""type"":""}]}}"; 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