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 = @"(.*?<LOC0:DBUG>.*|.*?<USER:DBUG>.*|.*?<SYSD:ERRR>.*?(localhost authd: Logout \(timeout\)|localhost authd.*?Terminal Services compatibility mode.*?).*|.*?<(SAU.|SYSD):INFO>.*|.*?<(SAU2|USER):NOTE>.*)"; string input = @"04 24 2019 10:38:08 10.62.181.191 <LOC0:DBUG> Apr 24 10:38:08 7A5B3SRVSWMGR01 safeguarding[6351]: RadarLite alerts - Start 04 23 2019 13:54:15 10.62.63.21 <USER:DBUG> Apr 23 13:54:15 localhost trafficlogger: cant stat classnames! 04 23 2019 14:05:26 10.62.63.21 <SYSD:ERRR> Apr 23 14:05:26 localhost authd: Logout (timeout); address 10.62.74.83, username CYMRU\CTT_McKessonSrvAcc, method NTLM authentication (Terminal Services compatibility mode) 04 23 2019 14:05:25 10.62.63.21 <SAU1:INFO> Apr 23 14:05:25 localhost sshd[29491]: Disconnected from 10.62.181.191 port 42412 04 23 2019 14:05:18 10.62.63.21 <SAU1:INFO> Apr 23 14:05:18 localhost sshd[29388]: Received disconnect from 10.62.181.191 port 42358:11: disconnected by user 04 23 2019 14:05:18 10.62.63.21 <SAU1:INFO> Apr 23 14:05:18 localhost sshd[29391]: Accepted publickey for replication from 10.62.181.191 port 42362 ssh2: DSA SHA256:g1/CZCWVxa2uFJpHF1M6vBaNKPk/NjazYr3vTonagbc 04 23 2019 14:05:12 10.62.63.21 <LOC0:DBUG> Apr 23 14:05:12 localhost safeguarding[7272]: Alert user Email/SMS 04 26 2019 10:19:24 10.62.63.21 <USER:NOTE> Apr 26 10:19:24 localhost smoothwall: Completing replication block 01556270336 04 26 2019 10:18:23 10.62.63.21 <USER:NOTE> Apr 26 10:18:23 localhost smoothwall: Duplicating Changes 01556270276 04 26 2019 10:20:57 10.62.181.191 <USER:NOTE> Apr 26 10:20:57 7A5B3SRVSWMGR01 smoothwall: Replication to child 10.62.181.192 changes 01556270457 04 26 2019 10:29:23 10.62.63.21 <USER:NOTE> Apr 26 10:29:23 localhost smoothwall: Starting replication block 01556270936 04 26 2019 11:23:17 10.62.181.191 <SAU2:NOTE> Apr 26 11:23:17 7A5B3SRVSWMGR01 sudo: datastore : TTY=unknown ; PWD=/ ; USER=root ; COMMAND=/usr/bin/datastore_update_hardlinks 09 05 2019 16:09:15 10.62.181.192 <SYSD:ERRR> Sep 5 16:09:15 localhost authd: Login; address 10.62.182.165, username CYMRU\ia039398, method NTLM authentication (Terminal Services compatibility mode) 09 05 2019 16:08:20 10.62.181.192 <SYSD:ERRR> Sep 5 16:08:20 localhost authd: Login; address 10.62.182.135, username CYMRU\Re111052, method NTLM authentication (Terminal Services compatibility mode) 09 05 2019 16:06:34 10.62.181.192 <SYSD:ERRR> Sep 5 16:06:34 localhost authd: Login; address 10.62.180.125, username CYMRU\Ne036088, method NTLM authentication (Terminal Services compatibility mode) 09 05 2019 09:04:41 10.69.137.81 <SYSD:INFO> 2019:09:05-09:04:40 wf-tg-utm-2 httpproxy[26178]: id=""0001"" severity=""info"" sys=""SecureWeb"" sub=""http"" name=""http access"" action=""pass"" method=""GET"" srcip=""10.69.200.24"" dstip="" user="" group="" ad_domain="" statuscode=""200"" cached=""1"" profile=""REF_HttProContaInterNetwo4 (Clients (DHCP/Static))"" filteraction=""REF_HttCffWbsBlock (WBS Block)"" size=""8365"" request=""0xdaedee00"" url=""http://download.windowsupdate.com/c/msdownload/update/others/2019/05/28899896_af8426aef8898787eb12d87b445645febda3def8.cab"" referer="" error="" authtime=""0"" dnstime=""0"" aptptime=""65"" cattime=""0"" avscantime=""0"" fullreqtime=""563"" device=""0"" auth=""2"" ua=""Windows-Update-Agent/10.0.10011.16384 Client-Protocol/2.0"" exceptions=""av,auth,content,url,ssl,certcheck,certdate,mime,fileextension,size,patience"""; 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