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"
"

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?P<device>\w+-\w+)\s+(?P<ObjectDetected>\w+.\w+.\w+.\w+.)(?P<date>\w+,\s+\w+\s+\d+,\s+\d+)\s+(?P<time>\d+:\d+:\d+\s+\w{1,2})\s+(?P<Path>[A-Z]:\\.+)\s+(?P<Type>Trojan|Virus|Worm)\s+((?P<Action>).+)((?P<Account>)((DOTIN\\)).+)\s+(?P<AVApplication>(Kaspersky).+)(?P<version>\d+.\d+.\d+.\d+)\s+((?P<Visibledate>(Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Friday,))\s+(January|February|March|April|May|June|July|August|September|October|November|December)\s+(\d+,\s+\d+\s+\d+:\d+:\d+\s+\w+))\s((?P<lastConnection>(Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Friday,))\s+(January|February|March|April|May|June|July|August|September|October|November|December)\s+\d+,\s+\d+\s+\d+:\d+:\d+\s+(PM|pm|AM|am))\s+(?P<IP>\d+.\d+.\d+.\d+)\s+(?P<ClientName>\w+-\w+)\s+(?P<Domain>\w+)"; string input = @"10.20.10.0 AMIRI-PC Trojan.Win32.Waldek.ajd Wednesday, January 27, 2016 8:05:18 AM E:\​ \​{0732260D-4643-427C-A22B-F0DFA8EDE30D}.{EE225B7C-E421-47D2-A65B-AE9AB046A5F2} Trojan Result: Untreated: Trojan.Win32.Waldek.ajd User: DOTIN\​t.amiri (Active user) Object: e:\​ \​{0732260d-4643-427c-a22b-f0dfa8ede30d}.{ee225b7c-e421-47d2-a65b-ae9ab046a5f2} DOTIN\​T.AMIRI Kaspersky Endpoint Security 10 Service Pack 1 for Windows 10.2.2.10535 Monday, February 15, 2016 3:11:38 PM Monday, February 15, 2016 3:11:38 PM 10.20.10.28 AMIRI-PC DOTIN ------------------------------------------------------------ (^Trojan) ((DOTIN\\)(w+.\w+))\s+(kaspersky) (Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Fridy,) &&(\s+(February)|)\s+\d+\s+\d+,\s+\d+\s+(\d+:\d+:\d+\s+\w+\s+\w+ (?P<Type>Trojan|Virus|Worm) +(?P<Account>) (?P<AVApplication> ?P<Visible>(Monday,|Saturday,|Sunday,|Tuesday,|Wednesday,|Thursday,|Friday,)\s+(January|February|March|April|May|June|July|August|September|October|November|December) ?P<version> ?P<lastConnection>\"; 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