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

$re = '/(?\'gPatSyslogPRI\'<\d+>) (?\'gPatMesgBody\'.*) (?\'gPatMesgBodyMin\'.*?) (?\'gPatSyslogNGHeader\'\w{3}\s+\d{1,2}\s\d{1,2}:\d{1,2}:\d{1,2}\s\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}) (?\'gPatMon\'Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec|\d{1,2}) (?\'gPatMonNum\'\d{1,2}) (?\'gPatDay\'\d{1,2}) (?\'gPatTime\'\d{1,2}:\d{1,2}:\d{1,2}) (?\'gPatYear\'\d{2,4}) (?\'gPatMSec\'\d{1,3}) (?\'gPatTimeMSec\'\d{1,2}:\d{1,2}:\d{1,2}\.\d{1,3}) (?\'gPatTimeZone\'Z|UTC|[+-]\d{1,2}:?\d{2}) (?\'gPatWeekday\'Mon|Tue|Wed|Thu|Fri|Sat|Sun) (?\'gPatIpV4Dot\'\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}) (?\'gPatIpAddr\'[0-9A-Fa-f]{0,4}(?::[0-9A-Fa-f]{0,4}){1,5}:(?:\d{1,3}(?:\.\d{1,3}){3}|[0-9A-Fa-f]{0,4}(?::[0-9A-Fa-f]{0,4})?)|\d{1,3}(?:\.\d{1,3}){3}) (?\'gPatIpPort\'\d{1,5}) (?\'gPatProto\'ftp|icmp|tcp|udp|http|ip|smb|smtp|snmp|others|FTP|ICMP|UDP|TCP|HTTP|IP|SMB|SMTP|SNMP|OTHERS) (?\'gPatFqdn\'\w+[.\w+]+) (?\'gPatWord\'\w+) (?\'gPatStr\'[^\s]*) (?\'gPatHostName\'[\w.-]+) (?\'gPatStrComma\'[^,]*) (?\'gPatStrLeftParen\'[^\(]*) (?\'gPatStrRightSB\'[^\]]*) (?\'gPatInt\'\d+) (?\'gPatSpace\'\s+) (?\'gPatStrEndColon\'[^:]*) (?\'gPatStrSQ\'[^\']*) (?\'gPatStrDQ\'[^\']*) (?\'gPatSentence\'\w[\s+\w]*)/m'; $str = ''; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php