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

r"
"
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\""Comment\"": \""(.*?)\"""; string input = @"[{""Comment"": ""Tbh the chair should\u2019ve had 4 pistons so Michael could finally eat at the table"", ""Likes"": ""4.4K"", ""Time"": ""2 years ago"", ""UserLink"": ""https://www.youtube.com/channel/UC_aU3uhZDInQSUUosL2uQ9A"", ""user"": ""Nates""}, {""Comment"": ""I want to believe that this isn't a screen personality and he is just a genuine sociopath"", ""Likes"": ""4.3K"", ""Time"": ""7 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCQBxoqlTxL2YNIm_p6FAEfw"", ""user"": ""tank head""}, {""Comment"": ""Can you build a chair that when you say \u201cI\u2019d like to make an announcement.\u201d Pistons push the chair up to make you taller than everyone else"", ""Likes"": ""1.9K"", ""Time"": ""7 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UC3HyXTP6aLjcZp88iOuytpg"", ""user"": ""Kitsune""}, {""Comment"": ""the tazer desk could easily be converted to a torture bed"", ""Likes"": ""245"", ""Time"": ""3 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCySFNMcZJm4MWAfiaIRpqvg"", ""user"": ""Cpt_Azure""}, {""Comment"": ""I want to imagine that his friends are just locked up in a house threatened hostage and forced to test his robot inventions"", ""Likes"": ""1.8K"", ""Time"": ""1 year ago"", ""UserLink"": ""https://www.youtube.com/channel/UCHZ6qYCGHm44ge2OGGazSVw"", ""user"": ""W""}, {""Comment"": ""\""I spent 12 hours making this...\""And 11 months tracking a goldfish in a cage..."", ""Likes"": ""492"", ""Time"": ""3 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCpNND06DunvPMGrSQqjjM_Q"", ""user"": ""Joshbobosh""}, {""Comment"": ""He should've added a delay to the chair so people get lured into a false sense of security"", ""Likes"": ""4.7K"", ""Time"": ""1 year ago"", ""UserLink"": ""https://www.youtube.com/channel/UCESk3Y2OfMMIgfATOsujI6Q"", ""user"": ""AshIsHere""}, {""Comment"": ""It's funny how Yvonne says \""Is that an electric chair?!\"", And then he goes and builds one like a year later"", ""Likes"": ""3K"", ""Time"": ""11 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCol-DCuwRT0sS98uBu1oCBA"", ""user"": ""MrMoo1452""}, {""Comment"": ""\u201cThat is a fuCKING alarm clock.\u201dI love that quote so much"", ""Likes"": ""919"", ""Time"": ""6 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCuVPAzq8ORnoK8CcEDpTmHA"", ""user"": ""Bababooey""}, {""Comment"": ""I had an art teacher who said, \""Don't lean on the table!\"" She was very angry when people did, and I'm assuming she would actually use the tazer table."", ""Likes"": ""79"", ""Time"": ""5 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCCzciQr3PjMlYqbMmyjtgDg"", ""user"": ""Tom Kas""}, {""Comment"": ""Make your windshield wipers, automatically wipe in the beat of the music that is played in the car."", ""Likes"": ""3.4K"", ""Time"": ""1 year ago"", ""UserLink"": ""https://www.youtube.com/channel/UCUfdOys12cHo7waaWkjG4mA"", ""user"": ""Benni B.""}, {""Comment"": ""Make a robot that automatically \u201cpermanently removes\u201d people who suggest an idea for a robot"", ""Likes"": ""84"", ""Time"": ""3 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCOh33A3iLMokwaUXI0Y6e6g"", ""user"": ""Swish_Cheetah""}, {""Comment"": ""I like that Michael calls us his \""worst, most hated enemies\"".\nYou can really feel the love."", ""Likes"": ""900"", ""Time"": ""2 years ago"", ""UserLink"": ""https://www.youtube.com/channel/UCeOSKFvurM-glO4TW8SX3EA"", ""user"": ""Camera Lizard""}, {""Comment"": ""\""Make a robot that poops cereal\""shredded\""Make a robot that piss beer\""genius"", ""Likes"": ""361"", ""Time"": ""11 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCbSIk0yT8w-sVCI_wNsQkPA"", ""user"": ""Ghedo""}, {""Comment"": ""ya gotta love the fact that the taser desk was acting as an EMP that caused his monitor to shut off several times"", ""Likes"": ""626"", ""Time"": ""10 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCmqGYYVwZ0nrd5tIxazWddA"", ""user"": ""Jackie""}, {""Comment"": ""I like that the Taser Desk incorporates so much high voltage garbage that it\u2019s making the electronics in his computer spaz out lmao. Who doesn\u2019t love a bad homemade EMP"", ""Likes"": ""4"", ""Time"": ""12 days ago"", ""UserLink"": ""https://www.youtube.com/channel/UCfvtdRAITOtzjZIgoKmCK5w"", ""user"": ""SilentGuy""}, {""Comment"": ""The fact everyone fears Michael is just hilarious"", ""Likes"": ""224"", ""Time"": ""7 months ago"", ""UserLink"": ""https://www.youtube.com/channel/UCzdTkBuxvZhOGQAN6eUsfWA"", ""user"": ""ipikalive""}, {""Comment"": ""I love how the taser desk literally constantly has sparks coming off of it which looks amazing, this is all thanks to that one comment"", ""Likes"": ""34"", ""Time"": ""3 months ago (edited)"", ""UserLink"": ""https://www.youtube.com/channel/UC_P1bdtzQhDgAnEZn1TyoBw"", ""user"": ""So confused""}, {""Comment"": ""Build something that looks absolutely terrifying but does nothing and just makes your friends paranoid"", ""Likes"": ""29K"", ""Time"": ""2 years ago"", ""UserLink"": ""https://www.youtube.com/channel/UCqMzTW0oC7B7HM6v8iiWIpg"", ""user"": ""Jerry Kat""}, {""Comment"": ""I love how everyone Michael knows is immediately scared when he talks to them"", ""Likes"": ""403"", ""Time"": ""1 year ago"", ""UserLink"": ""https://www.youtube.com/channel/UCqHG4WQJ7S3tUUo895WFBtQ"", ""user"": ""Evan Thorne""}]"; 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