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

Substitution

Processing...

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?P<date>\S{3}\s\d{1,3}\s\d{2}\:\d{2}\:\d{2})\s(?P<device>\S+)\s\S\=(?P<src>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})\:\s\S\=\""(?P<user>.*?)\""\s\S\=\d+\s\S\=\S\s\S\=\d+\s\S\=\d+\s\S+\=\d\s\S{1,3}\=.*?type=\"".*?\""\s.*?meth=(?P<type>\S+)\s\S+\=\""(?P<url>.*?)\""\s\S{2}\=\""(?P<agent>.*?)\""\s\S{1,3}\=\""(?P<url2>.*?)dom\=\""(?P<domain>.*?)\"".*?target_ip\=\""(?P<dest>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})\"".*"; string substitution = @""; string input = @"Oct 18 06:27:03 WS2000.wnins.com h=172.16.20.74: u=""WNINS\\rehetzel"" s=200 X=+ t=1445149621 T=44767 Ts=0 act=1 cat=""0x2200000008"" app=""-"" rsn=- threat=""-"" type=""image/jpeg"" ctype=""image/jpeg"" sav-ev=- sav-dv=- uri-dv=- cache=- in=471 out=990 meth=GET ref=""http://www.techrepublic.com/blog/the-enterprise-cloud/how-do-i-assign-permissions-to-users-to-see-sql-agent-jobs/"" ua=""Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.99 Safari/537.36"" req=""GET http://d.pzkysq.pink/5ET3nslK.jpg?z=715211411411 HTTP/1.1"" dom=""pzkysq.pink"" filetype=""-"" rule=""0"" filesize=518 axtime=0.000455 fttime=0.000043 scantime=- src_cat=""0x2000000008"" labs_cat=""0x2000000008"" dcat_prox=""-"" target_ip=""204.93.43.48"" labs_rule_id=""0"" reqtime=0.000 adtime=0.000000 ftbypass=- os=Windows authn=17 auth_by=ntlm dnstime=0.000009 quotatime=-"; Regex regex = new Regex(pattern); string result = regex.Replace(input, substitution, 1); } }

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