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 = @"(?<wholekey>(?s)^\[.*?\].*?(?=^\[|\z))"; string input = @"Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE] ""ServiceLastKnownStatus""=dword:00000002 [HKEY_LOCAL_MACHINE\BCD00000000] [HKEY_CURRENT_USER\AppEvents\Schemes\Apps\.Default\Notification.Default\.Current] @=""C:\\Windows\\media\\Windows Notify System Generic.wav"" [HKEY_LOCAL_MACHINE\BCD00000000\Description] ""KeyName""=""BCD00000000"" ""TreatAsSystem""=dword:00000001 ""GuidCache""=hex:f4,60,9c,00,7b,c3,da,01,03,27,00,00,8a,d6,94,57,42,4c,7f,29,8a,\ 00,00,00 ""Element""=hex:00 ""Element""=hex(7):7b,00,37,00,65,00,61,00,32,00,65,00,31,00,61,00,63,00,2d,00,\ 32,00,65,00,36,00,31,00,2d,00,34,00,37,00,32,00,38,00,2d,00,61,00,61,00,61,\ 00,33,00,2d,00,38,00,39,00,36,00,64,00,39,00,64,00,30,00,61,00,39,00,66,00,\ 30,00,65,00,7d,00,00,00,00,00 ""Type""=dword:101fffff ""Element""=""EFI PXE 0 for IPv4 (74-5D-22-21-B1-95) "" ""OSMaxVersionTested""=hex(b):00,00,ff,3f,00,00,0a,00 ""OSMinVersion""=hex(b):00,00,00,00,00,00,0a,00 ""WMP11.AssocFile.3G2""=hex(0): ""Drivers""=hex(100000): ""DriverType""=hex(200000): ""lParam""=hex(4):00,00,00,00,00,00,00,00 [HKEY_LOCAL_MACHINE\BCD00000000\Objects\{3edef9e6-2f6e-11ef-968a-9457424c7f29}\Elements] [HKEY_LOCAL_MACHINE\BCD00000000\Objects\{3edef9e9-2f6e-11ef-968a-9457424c7f29}] ""command""=hex(2):22,00,25,00,70,00,72,00,6f,00,67,00,72,00,61,00,6d,00,46,00,\ 69,00,6c,00,65,00,73,00,25,00,5c,00,57,00,69,00,6e,00,64,00,6f,00,77,00,73,\ 00,20,00,4d,00,61,00,69,00,6c,00,5c,00,57,00,61,00,62,00,2e,00,65,00,78,00,\ 65,00,22,00,20,00,2f,00,43,00,72,00,65,00,61,00,74,00,65,00,43,00,6f,00,6e,\ 00,74,00,61,00,63,00,74,00,20,00,22,00,25,00,31,00,22,00,00,00 ""PrimaryLineOutTopo""=hex(40007):41,00,70,00,6f,00,50,00,72,00,65,00,73,00,65,\ 00,74,00,31,00,00,00,00,00 ""Element""=hex(7):7b,00,31,00,61,00,66,00,61,00,39,00,63,00,34,00,39,00,2d,00,\ 31,00,36,00,61,00,62,00,2d,00,34,00,61,00,35,00,63,00,2d,00,39,00,30,00,31,\ 00,62,00,2d,00,32,00,31,00,32,00,38,00,30,00,32,00,64,00,61,00,39,00,34,00,\ 36,00,30,00,7d,00,00,00,00,00 ""Isa""=hex(8):01,00,00,00,01,00,00,00,00,00,00,00,00,00,00,00,28,00,00,00,01,01,\ 00,00,00,00,00,00,00,00,00,00,00,01,00,00,01,03,00,00,e8,42,00,00,00,00,00,\ 00,08,00,00,00,01,03,00,00,e8,4a,00,00,00,00,00,00,08,00,00,00,01,03,00,00,\ e8,82,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,86,00,00,00,00,00,00,08,\ 00,00,00,01,03,00,00,e8,8a,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,8e,\ 00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,92,00,00,00,00,00,00,08,00,00,\ 00,01,03,00,00,e8,96,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,9a,00,00,\ 00,00,00,00,08,00,00,00,01,03,00,00,e8,9e,00,00,00,00,00,00,08,00,00,00,01,\ 03,00,00,e8,a2,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,a6,00,00,00,00,\ 00,00,08,00,00,00,01,03,00,00,e8,aa,00,00,00,00,00,00,08,00,00,00,01,03,00,\ 00,e8,ae,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,b6,00,00,00,00,00,00,\ 08,00,00,00,01,03,00,00,e8,ba,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,\ be,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,c2,00,00,00,00,00,00,08,00,\ 00,00,01,03,00,00,e8,c6,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,ca,00,\ 00,00,00,00,00,08,00,00,00,01,03,00,00,e8,ce,00,00,00,00,00,00,08,00,00,00,\ 01,03,00,00,e8,d2,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,d6,00,00,00,\ 00,00,00,08,00,00,00,01,03,00,00,e8,da,00,00,00,00,00,00,08,00,00,00,01,03,\ 00,00,e8,de,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,e2,00,00,00,00,00,\ 00,08,00,00,00,01,03,00,00,e8,e6,00,00,00,00,00,00,08,00,00,00,01,03,00,00,\ e8,ea,00,00,00,00,00,00,08,00,00,00,01,03,00,00,e8,ee,00,00,00,00,00,00,08,\ 00,00,00,01,03,00,00,ee,f6,00,00,00,00,00,00,02,00,00,00,01,03,00,00,ee,fa,\ 00,00,00,00,00,00,02,00,00,00,01,03,00,00,ee,fe,00,00,00,00,00,00,02,00,00,\ 00,02,03,00,00,03,00,00,00,03,00,00,00,ff,ff,ff,ff,02,03,00,00,04,00,00,00,\ 04,00,00,00,ff,ff,ff,ff,02,03,00,00,0e,00,00,00,0e,00,00,00,ff,ff,ff,ff,02,\ 03,00,00,06,00,00,00,06,00,00,00,ff,ff,ff,ff,02,03,00,00,0c,00,00,00,0c,00,\ 00,00,ff,ff,ff,ff,02,03,00,00,01,00,00,00,01,00,00,00,ff,ff,ff,ff,03,03,00,\ 00,ff,ff,bf,ff,00,00,00,00,00,00,40,00 ""Configuration Data""=hex(9):ff,ff,ff,ff,ff,ff,ff,ff,00,00,00,00,02,00,00,00,05,\ 00,00,00,0c,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,ff,ff,ff,ff,\ 00,00,ff,ff,01,00,05,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\ 00 ""Pci""=hex(a):e8,01,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\ 00,00,00,00,00,00,01,00,00,00,01,00,01,00,0e,00,00,00,00,01,00,00,00,00,00,\ 00,00,00,00,00,00,00,00,00,00,00,01,00,00,00,00,00,ff,ff,ff,ff,00,00,00,00,\ 08,01,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,05,00,00,00,00,00,00,ff,\ ff,00,00,00,00,00,00,08,01,00,00,00,00,00,00,00,00,00,00,00,00,00,00,40,01,\ 00,00,00,00,00,00,7f,01,00,00,00,00,00,00,08,01,00,00,00,00,00,00,00,00,00,\ 00,00,00,00,00,00,02,00,00,00,00,00,00,ff,02,00,00,00,00,00,00,08,01,00,00,\ 00,00,00,00,00,00,00,00,00,00,00,00,00,03,00,00,00,00,00,00,6f,03,00,00,00,\ 00,00,00,08,01,00,00,00,00,00,00,00,00,00,00,00,00,00,00,78,03,00,00,00,00,\ 00,00,7a,03,00,00,00,00,00,00,08,01,00,00,00,00,00,00,00,00,00,00,00,00,00,\ 00,e8,02,00,00,00,00,00,00,ff,02,00,00,00,00,00,00,08,01,00,00,00,00,00,00,\ 00,00,00,00,00,00,00,00,f0,01,00,00,00,00,00,00,f8,01,00,00,00,00,00,00,08,\ 01,00,00,00,00,00,00,00,00,00,00,00,00,00,00,b0,03,00,00,00,00,00,00,cf,03,\ 00,00,00,00,00,00,08,01,00,00,00,00,00,00,00,00,00,00,00,00,00,00,e8,03,00,\ 00,00,00,00,00,ff,03,00,00,00,00,00,00,08,01,00,00,00,00,00,00,00,00,00,00,\ 00,00,00,00,ce,01,00,00,00,00,00,00,cf,01,00,00,00,00,00,00,08,01,00,00,00,\ 00,00,00,00,00,00,00,00,00,00,00,00,01,00,00,00,00,00,00,ff,03,00,00,00,00,\ 00,00,00,03,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,10,00,00,00,00,\ 00,ff,ff,ff,ff,ff,ff,ff,ff,08,03,00,00,00,00,00,00,00,00,00,00,00,00,00,00,\ 00,00,08,00,00,00,00,00,ff,ff,0d,00,00,00,00,00"; 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