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

/
/
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"((asia|europe|us|australia)|((north|south)(america|africa)))-((east|west|central|north|south)|((north|south)(east)))([0-9]{1,2})"; string input = @"(east|west|central|north)?(north|south)?(east)[0-9]{1,2} (east|west|central|north)(north|south)(east)[0-9]{1,2} (north|south)(america) FireStore Regions us-west1 oregon us-west2 Los Angeles us-west3 Tuz Gölü şehri us-west4 Las Vegas northamerica-northeast1 Montreal northafrica-west3 southafrica-east1 us-east1 Güney Carolina us-east4 Kuzey Virginia southamerica-east1 Sao Paulo europe-west2 Londra europe-west4 europe-west3 Frankfurt europe-central2 Varşova europe-west6 Zürih asia-south1 Bombay asia-southeast1 Singapur asia-southeast2 Cakarta asia-east2 Hong Kong asia-east1 Tayvan asia-northeast1 Tokyo asia-northeast2 Osaka asia-northeast3 Seul australia-southeast1 Sidney australia-southeast2 australia-southeast Function Regions asia-east1 (Tayvan) asia-east2 (Hong Kong) asia-northeast1 (Tokyo) asia-northeast2 (Osaka) europe-west1 (Belçika) europe-west2 (Londra) us-central1 (Iowa) us-east1 (Güney Karolina) us-east4 (Kuzey Virginia) us-west1 (Oregon) asia-northeast3 (Seul) asia-southeast1 (Singapur) asia-southeast2 (Cakarta) asia-south1 (Mumbai) australia-southeast1 (Sidney) europe-central2 (Varşova) europe-west3 (Frankfurt) europe-west6 (Zürih) northamerica-northeast1 (Montreal) southamerica-east1 (Sao Paulo) us-west2 (Los Angeles) us-west3 (Salt Lake City) us-west4 (Las Vegas) asia-east1 (Tayvan) us-west2 (Los Angeles) europe-west1 (Belçika) us-west3 (Salt Lake City) asia-northeast1 (Tokyo) southamerica-east1 (Sao Paulo) us-west4 (Las Vegas) asia-east2 (Hong Kong) northamerica-northeast1 (Montreal) europe-west2 (Londra) asia-south1 (Mumbai) europe-west3 (Frankfurt) us-central1 (Iowa) europe-central2 (Varşova) europe-west6 (Zürih) us-east1 (Güney Karolina) asia-northeast3 (Seul) us-east4 (Kuzey Virginia) australia-southeast1 (Sidney) us-west1 (Oregon) asia-southeast2 (Cakarta) asia-southeast1 (Singapur)"; 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