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

/
/

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"gamers_online.*\s*(\d+),?(\d+),?(\d+)"; string input = @"[...] <div id=""about_header_area"" class="" global""> <div class=""about_area_inner_wrapper""> <div id=""about_monitor_video""> <video width=""100%"" height=""auto"" autoplay muted loop playsinline poster=""https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.png""> <source src=""https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.webm"" type=""video/webm""> <source src=""https://cdn.fastly.steamstatic.com/store/about/videos/about_hero_loop_web.mp4"" type=""video/mp4""> </video> <div id=""about_monitor_video_gradient""></div> </div> <div id=""about_header""> <div id=""about_greeting""> <div class=""about_greeting_header""> <div class=""steam_logo""><img src=""https://cdn.fastly.steamstatic.com/store//about/logo_steam.svg"" alt=""The logo for Steam""></div> <div class=""about_subtitle"">Steam is the ultimate destination for playing, discussing, and creating games.</div> <div class=""online_stats""> <div class=""online_stat""> <div class=""online_stat_label gamers_online"">online</div> 36,426,658 </div> <div class=""online_stat""> <div class=""online_stat_label gamers_in_game"">playing now</div> 10,289,777 </div> </div> </div> <div class=""about_install_wrapper""> <div class=""about_install win ""> <a href=""https://cdn.fastly.steamstatic.com/client/installer/SteamSetup.exe"" class=""about_install_steam_link"">Install Steam</a> </div> <div class=""installer_list""> <div class=""available_platforms""> Also available on: </div> <a class=""platform_icon"" href=""https://cdn.fastly.steamstatic.com/client/installer/steam.dmg""> <img src=""https://cdn.fastly.steamstatic.com/store/about/icon-macos.svg""> </a> <a class=""platform_icon"" href=""https://cdn.fastly.steamstatic.com/client/installer/steam.deb""> <img src=""https://cdn.fastly.steamstatic.com/store/about/icon-steamos.svg""> </a> <a class=""platform_icon"" href=""https://support.google.com/chromebook?p=steam_on_chromebook""> <img src=""https://cdn.fastly.steamstatic.com/store/about/icon-chromeos.svg""> </a> </div> </div> </div> </div> </div> <div class=""learn_more_btn""> <a href=""#about_games_cta_area"" class=""smooth_scroll""> Learn more <span class=""down_arrow""></span> </a> </div> </div> "; Match m = Regex.Match(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