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 = @"(?<timestamp>^.{19})\s\S+\s\S+\s(?<method>\S+)\s(?<w_path>\S*\/)(?<file>\S*)\s(?<var>\S+?)(\s|(\|.+\|)(?<error>\S+)\s)(?<dport>\S+)\s\S\s(?<sip>\S+)\s(?<agent>\S+)\s(?<status>\S+).+"; string input = @"2011-01-12 15:42:36 W3SVC1499154376 123.45.48.11 GET /main/view.asp - 80 - 210.177.175.190 Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.1;+Trident/4.0;+SLCC2;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30729;+Media+Center+PC+6.0) 200 0 0 2011-01-12 15:42:36 W3SVC1499154376 123.45.48.11 GET /main/viewasp - 80 - 210.177.175.190 Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.1;+Trident/4.0;+SLCC2;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30729;+Media+Center+PC+6.0) 200 0 0 2011-01-12 15:42:36 W3SVC1499154376 123.45.48.11 GET /view.asp cate_id=2&vod_id=784 80 - 210.177.175.190 Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.1;+Trident/4.0;+SLCC2;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30729;+Media+Center+PC+6.0) 200 0 0 2011-01-12 15:42:36 W3SVC1499154376 123.45.48.11 GET / - 80 - 210.177.175.190 Mozilla/4.0+(compatible;+MSIE+8.0;+Windows+NT+6.1;+Trident/4.0;+SLCC2;+.NET+CLR+2.0.50727;+.NET+CLR+3.5.30729;+.NET+CLR+3.0.30729;+Media+Center+PC+6.0) 200 0 0 2011-01-12 15:42:36 W3SVC1499154376 123.45.48.11 GET /view.asp cate_id=2&vod_id=784%20and%200%3C(select%20top%201%20cast([name]%20as%20nvarchar(256))%2bchar(94)%20from(select%20top%20%201%20dbid,name%20from%20[master].[dbo].[sysdatabases]%20order%20by%20[dbid])%20t%20order%20by%20[dbid]%20desc)--|107|80040e14|'('_근처의_구문이_잘못되었습니다. 80 - 210.177.175.190 pangolin/2.0 500 0 0"; 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