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 = @".\w+\W+(?<EventTime>[^""]+)\W+\w+\W+(?<HostName>\w+).+?EventID\W+(?<EventID>\w+).+?Message\W+(?<Message>[^""]+).+"; string input = @"""EventTime"":""2017-08-11 10:40:07"",""Hostname"":""School4"",""Keywords"":-9187343239835811840,""EventType"":""INFO"",""SeverityValue"":2,""Severity"":""INFO"",""EventID"":7036,""SourceName"":""Service Control Manager"",""ProviderGuid"":""{555908D1-A6D7-4695-8E1E-26931D2012F4}"",""Version"":0,""Task"":0,""OpcodeValue"":0,""RecordNumber"":263066,""ProcessID"":548,""ThreadID"":7528,""Channel"":""System"",""Message"":""Application Experience 서비스가 중지 상태로 들어갔습니다."",""param1"":""Application Experience"",""param2"":""중지"",""EventReceivedTime"":1502415607,""SourceModuleName"":""in"",""SourceModuleType"":""im_msvistalog"""; 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