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 = @"div id=^(.*)><"; string input = @"<div style=""outline: 1px solid blue;"" class=""_36bx _4-u2 _4-u8"" data-testid=""react-composer-root"" id=""u_0_18"" data-reactid="".4""><div class=""_4d6h _4p1p _4-u3 _57d8"" data-reactid="".4.0""><div class=""clearfix"" data-reactid="".4.0.0""><div class=""_ohe lfloat"" data-reactid="".4.0.0.$left""><div data-reactid="".4.0.0.$left.0""><a class=""_5qtm _5qtn"" role=""tab"" aria-selected=""true"" label=""Statut"" icon=""[object Object]"" data-testid=""status-attachment-selector"" selected="" href=""#"" data-reactid="".4.0.0.$left.0.0""><span class=""_4-fs"" data-reactid="".4.0.0.$left.0.0.0""><i class=""_5qto img sp_QiW5hJ5PiNH sx_49d0b1"" data-reactid="".4.0.0.$left.0.0.0.0""></i><span class=""_5qtp"" data-reactid="".4.0.0.$left.0.0.0.1"">Statut</span><span class=""_5qtq"" data-reactid="".4.0.0.$left.0.0.0.2""></span></span></a><a class=""_5qtm"" role=""tab"" aria-selected=""false"" label=""Photo/vidéo"" icon=""[object Object]"" data-testid=""media-attachment-selector"" href=""#"" data-reactid="".4.0.0.$left.0.1""><span class=""_4-fs"" data-reactid="".4.0.0.$left.0.1.0""><i class=""_5qto img sp_QiW5hJ5PiNH sx_33bc4c"" data-reactid="".4.0.0.$left.0.1.0.0""></i><span class=""_5qtp"" data-reactid="".4.0.0.$left.0.1.0.1"">Photo/vidéo</span><span class=""_5qtq"" data-reactid="".4.0.0.$left.0.1.0.2""></span></span></a><a class=""_5qtm"" role=""tab"" aria-selected=""false"" label=""Offre, évènement +"" icon=""[object Object]"" href=""#"" data-reactid="".4.0.0.$left.0.2""><span class=""_4-fs"" data-reactid="".4.0.0.$left.0.2.0""><i class=""_5qto img sp_BaO-9AbAyUH sx_98a590"" data-reactid="".4.0.0.$left.0.2.0.0""></i><span class=""_5qtp"" data-reactid="".4.0.0.$left.0.2.0.1"">Offre, évènement +</span><span class=""_5qtq"" data-reactid="".4.0.0.$left.0.2.0.2""></span></span></a></div></div><div class=""_ohf rfloat"" data-reactid="".4.0.0.$right""><div data-reactid="".4.0.0.$right.0""><img class=""_4d6i img"" src=""https://static.xx.fbcdn.net/rsrc.php/v2/yb/r/GsNJNwuI-UM.gif"" data-reactid="".4.0.0.$right.0.0"" height=""11"" width=""16""><span data-reactid="".4.0.0.$right.0.1""><span class=""hidden_elem _5gvy img _55ym _55yn _55yo _5d9-"" aria-label=""Chargement..."" aria-busy=""true"" data-reactid="".4.0.0.$right.0.1.0""></span><span class=""_6vh _4w4v"" data-reactid="".4.0.0.$right.0.1.1""><span class=""hidden_elem _3-8_ img _55ym _55yn _55yo _5d9-"" aria-label=""Chargement..."" aria-busy=""true"" data-reactid="".4.0.0.$right.0.1.1.0""></span><span aria-label=""Vous publiez en tant que Mega drole"" data-hover=""tooltip"" data-reactid="".4.0.0.$right.0.1.1.1""><a aria-haspopup=""true"" aria-owns=""js_i"" style=""max-width:200px;"" class=""_4z8- _55pi _2agf _4z8- _55pi _4jy0 _4jy3 _517h _51sy _59pe _42ft"" href=""#"" type=""button"" data-reactid="".4.0.0.$right.0.1.1.1.0""><span class=""_55pe"" data-reactid="".4.0.0.$right.0.1.1.1.0.1""><img src=""https://fbcdn-profile-a.akamaihd.net/hprofile-ak-xft1/v/t1.0-1/p32x32/1453483_555123727915438_1286693911_n.png?oh=e520e64208f4829f8307cfadce0812e8&amp;oe=56C302F3&amp;__gda__=1456503974_001e2d51c40bce6e62c31d80438f25a9"" class=""img"" data-reactid="".4.0.0.$right.0.1.1.1.0.1.0"" height=""16"" width=""16""><span data-reactid="".4.0.0.$right.0.1.1.1.0.1.1""></span></span><i alt="" class=""_3-99 img sp_5_FvgObiY-v sx_593e27"" data-reactid="".4.0.0.$right.0.1.1.1.0.2""></i></a></span></span></span></div></div></div></div><div class=""_4zoz _4-u3"" data-reactid="".4.1""><div id=""js_k"" data-reactid="".4.1.0""><div class=""_1y-n"" data-reactid="".4.1.0.0""><div class=""_1y-o"" data-reactid="".4.1.0.0.0""><span class=""_1y-p"" data-reactid="".4.1.0.0.0.0"">Faites glisser un lien, des photos ou des vidéos ici</span><span class=""_1y-q"" data-reactid="".4.1.0.0.0.1"">Déposer le lien</span><span class=""_1y-r"" data-reactid="".4.1.0.0.0.2"">Déposer une photo/vidéo</span><span class=""_1y-s"" data-reactid="".4.1.0.0.0.3"">Déposez les photos</span></div></div><div class=""clearfix"" data-reactid="".4.1.0.1""><div class=""_42k7 _4bl7"" data-reactid="".4.1.0.1.$0""><div class=""_3hvt"" data-reactid="".4.1.0.1.$0.0""><img class=""_bth img"" src=""https://fbcdn-profile-a.akamaihd.net/hprofile-ak-xft1/v/t1.0-1/p40x40/1453483_555123727915438_1286693911_n.png?oh=531ded5fcd4f71ed763f8c6d683325a5&amp;oe=568FDCAF&amp;__gda__=1456525306_54b153b26c9b3c2c6a3ac05ebc0242d6"" data-reactid="".4.1.0.1.$0.0.0"" height=""40"" width=""40""></div></div><div class=""_4bl9"" data-reactid="".4.1.0.1.$1""><div class=""_1mwp _1mwq _5bu_ _5yk1"" data-reactid="".4.1.0.1.$1.0""><div class=""_5yk2"" tabindex=""-2"" data-reactid="".4.1.0.1.$1.0.0""><div class=""_5yw9"" data-reactid="".4.1.0.1.$1.0.0.0""><div class=""_5ywb _5ywc"" data-reactid="".4.1.0.1.$1.0.0.0.0""><div class=""_3br6"" data-reactid="".4.1.0.1.$1.0.0.0.0.0"">Écrivez quelque chose...</div></div><div class=""_5ywa"" data-reactid="".4.1.0.1.$1.0.0.0.$editor0""><div aria-autocomplete=""list"" aria-expanded=""false"" aria-haspopup=""false"" aria-owns=""js_j"" class=""_54-z"" role=""combobox"" spellcheck=""true"" title=""Écrivez quelque chose..."" data-reactid="".4.1.0.1.$1.0.0.0.$editor0.0"" contenteditable=""true""><div data-contents=""true"" data-reactid="".4.1.0.1.$1.0.0.0.$editor0.0.0""><div data-block=""true"" data-offset-key=""cioa-0-0"" class=""_209g _2vxa"" data-reactid="".4.1.0.1.$1.0.0.0.$editor0.0.0.$cioa""><span data-offset-key=""cioa-0-0"" data-reactid="".4.1.0.1.$1.0.0.0.$editor0.0.0.$cioa.0:$cioa-0-0""><br data-reactid="".4.1.0.1.$1.0.0.0.$editor0.0.0.$cioa.0:$cioa-0-0.0""></span></div></div></div></div></div></div></div></div></div><noscript data-reactid="".4.1.0.2""></noscript><div class=""_3qg0"" data-reactid="".4.1.0.4""></div><div data-reactid="".4.1.0.7""><div class=""_5f24"" data-reactid="".4.1.0.7.0""><noscript data-reactid="".4.1.0.7.0.1""></noscript><noscript data-reactid="".4.1.0.7.0.2""></noscript><noscript data-reactid="".4.1.0.7.0.3""></noscript></div><div class=""_2dck _4-u3 _57d8"" data-reactid="".4.1.0.7.1""><div class=""clearfix"" data-reactid="".4.1.0.7.1.0""><div class=""_ohe lfloat"" data-reactid="".4.1.0.7.1.0.$left""><div class=""_47gt"" data-reactid="".4.1.0.7.1.0.$left.0""><div class=""_3xem _3xen"" data-reactid="".4.1.0.7.1.0.$left.0.0""><div class=""_m _6a"" data-reactid="".4.1.0.7.1.0.$left.0.0.0""><a rel=""ignore"" data-hover=""tooltip"" aria-label=""Ajoutez des photos à votre publication"" class=""_3xen _50hp"" data-reactid="".4.1.0.7.1.0.$left.0.0.0.0""><span class=""accessible_elem"" data-reactid="".4.1.0.7.1.0.$left.0.0.0.0.0"">Ajoutez des photos</span><div class=""_3jk""><input id=""js_l"" aria-label=""Ajoutez des photos à votre publication"" multiple="" name=""composer_photo"" role=""button"" tabindex=""0"" class=""_n _5f0v"" data-reactid="".4.1.0.7.1.0.$left.0.0.0.1"" type=""file""></div></a></div></div><a data-hover=""tooltip"" class=""_3xem"" aria-label=""Ajoutez ce que vous faites ou votre humeur"" tabindex=""0"" role=""button"" data-reactid="".4.1.0.7.1.0.$left.0.2""><span class=""accessible_elem"" data-reactid="".4.1.0.7.1.0.$left.0.2.0"">Ajoutez ce que vous faites ou votre humeur</span><div class=""_3xen _3vk5"" data-reactid="".4.1.0.7.1.0.$left.0.2.1""></div></a><a data-hover=""tooltip"" class=""_3xem"" aria-label=""Ajoutez un lieu à votre publication"" tabindex=""0"" role=""button"" data-reactid="".4.1.0.7.1.0.$left.0.3""><span class=""accessible_elem"" data-reactid="".4.1.0.7.1.0.$left.0.3.0"">Identifier un lieu</span><div class=""_3xen _52xx"" data-reactid="".4.1.0.7.1.0.$left.0.3.1""></div><noscript data-reactid="".4.1.0.7.1.0.$left.0.3.2""></noscript></a><a data-hover=""tooltip"" class=""_3xem"" aria-label=""Définir la date et l’heure de votre publication"" tabindex=""0"" role=""button"" data-reactid="".4.1.0.7.1.0.$left.0.4""><span class=""accessible_elem"" data-reactid="".4.1.0.7.1.0.$left.0.4.0"">Définir la date et l’heure de votre publication</span><div class=""_3xen _2czx"" data-reactid="".4.1.0.7.1.0.$left.0.4.1""></div></a></div></div><div class=""_ohf rfloat"" data-reactid="".4.1.0.7.1.0.$right""><div class=""_2ph- _4-u3"" data-reactid="".4.1.0.7.1.0.$right.0""><button aria-label=""Mettez votre publication en avant pour atteindre plus de monde"" data-hover=""tooltip"" data-testid=""boosted_post_button_with_id"" class=""_4dyi _4jy0 _4jy3 _517h _51sy _42ft"" type=""submit"" value=""1"" data-reactid="".4.1.0.7.1.0.$right.0.0:$boosted_post_button""><span class=""_4m40"" data-reactid="".4.1.0.7.1.0.$right.0.0:$boosted_post_button.1"">Mettre en avant</span></button><div class=""_51xa"" data-reactid="".4.1.0.7.1.0.$right.0.2""><button class=""_1mf7 _4jy0 _4jy3 _4jy1 _51sy selected _42ft"" data-testid=""react-composer-post-button"" type=""submit"" value=""1"" data-reactid="".4.1.0.7.1.0.$right.0.2.0""><span data-reactid="".4.1.0.7.1.0.$right.0.2.0.1"">Publier</span></button><div class=""_lde uiPopover _6a _6b"" data-reactid="".4.1.0.7.1.0.$right.0.2.1""><button role=""button"" class=""_p _4jy0 _4jy3 _4jy1 _51sy selected _42ft"" type=""submit"" value=""1"" data-reactid="".4.1.0.7.1.0.$right.0.2.1.$/=10""><i class=""img sp_5_FvgObiY-v sx_a9190d"" data-reactid="".4.1.0.7.1.0.$right.0.2.1.$/=10.2""></i></button></div></div></div></div></div></div></div></div><noscript data-reactid="".4.1.1""></noscript><noscript data-reactid="".4.1.2""></noscript><noscript data-reactid="".4.1.$QUESTION""></noscript><noscript data-reactid="".4.1.$QANDA""></noscript></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