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 = @"^.*?]\s(?<severity>\w+)\s+(?<group>[^\[]+)\[logno=(?<object>\d+)\,\s+user=(?<login>\w+)\,\s+usid=(?<recipient>\w+)\,\s+msg=\""(?<reason>[^""]*)\""]$"; string input = @"10 23 2018 09:23:59 1.1.1.1 <LOC2:WARN> Oct 23 09:24:00 2018-10-23 09:24:00,076 [Thread-0] WARN EventLHost1d- UserSessNotification[STOP_TRANS, user=[name=admin, usid=72422, addr=127.0.0.1, prot=1], db=DB_RUNNING] 10 22 2018 17:07:48 1.1.4.1 <LOC2:WARN> Oct 22 17:08:00 2018-10-23 03: 08:00,393 [Thread-0] WARN EventLHost1d- AuditNotification[logno=103, user=admin, usid=0, msg=""Logged in over ssh using externalauth, member of groups: admin,auditor,manage-appliance,manage-pki,manage-policy""] 10 19 2018 12:36:18 1.1.1.1 <LOC2:WARN> Oct 19 12:36:19 2018-10-19 12: 36:19,112 [Thread-0] WARN EventLHost1d- UserSessNotification[STOP, user=[name=admin, usid=27572, addr=127.0.0.1, prot=1], db=DB_NONE] 10 22 2018 09:36:11 1.1.4.1 <LOC2:WARN> Oct 22 09:36:22 2018-10-22 19: 36:22,691 [Thread-0] WARN EventLHost1d- AuditNotification[logno=107, user=admin, usid=32891, msg=""Logged out from maapi ctx=webui (closed)""] 10 24 2018 09:31:54 1.1.1.1 <LOC2:ALRT> Oct 24 09:31:55 SSLCDMX Health monitoring: PROBLEM - SSLCDMX Metric: Load Utilization WARNING: Memory load is at 67.46%. - Capacity util=30.31% 10 22 2018 19:30:13 1.1.3.1 <LOC2:WARN> Oct 22 17:31:38 2018-10-22 17: 31:38,947 [Thread-0] WARN EventLHost1d- AuditNotification[logno=105, user=admin, usid=73051, msg=""assigned to groups: manage-policy,manage-pki,manage-appliance,auditor,admin""] 10 23 2018 22:46:23 1.2.3.1 <LOC2:ALRT> Oct 24 01:45:01 SSLREYNOSA root: Health Monitoring (cron): Trimmed event history to 30 days. 10 23 2018 10:04:05 1.1.1.1 <LOC2:WARN> Oct 23 10:04:06 2018-10-23 10: 04:06,531 [Thread-0] WARN EventLHost1d- AuditNotification[logno=105, user=Host2ez, usid=72793, msg=""assigned to groups: manage-pki""]"; 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