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
Processing...

Test String

Code Generator

Language

Generated Code

re = /(?m)^(?<time>.*?)\s(?<collector_IP_Address>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})\s\w+\:\s(?<Type>.*)#(?<Alert_id>.*),\sstart\s(?<start_time>.*),\sduration\s(?<duration>\d+),\sdirection\s(?<direction>\w+),\shost\s(?<host>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}),\ssignatures\s\((?<signatures>.*)\),\simpact\s(?<impact>.*),\simportance\s(?<importance>\d+),\smanaged_objects\s\(\"(?<managed_objects>\w+)\"\),\s\(parent\smanaged\sobject\s\"(?<parent_managed_object>\w+)\"\)/ str = 'Dec 5 18:04:51 192.168.69.50 pfsp: Host Detection alert #22049413, start 2017-12-06 00:03:45 GMT, duration 66, direction incoming, host 71.92.104.13, signatures (ICMP, IP Fragmentation, Total Traffic, UDP, DNS Amplification), impact 4.00 Gbps/386.20 Kpps, importance 2, managed_objects ("Tonga"), (parent managed object "nil") Dec 5 16:19:51 192.168.69.50 pfsp: Host Detection alert #22049331, start 2017-12-05 22:16:45 GMT, duration 186, direction incoming, host 24.177.66.30, signatures (ICMP, IP Fragmentation, TCP NULL, TCP SYN, TCP RST, Total Traffic, UDP), impact 310.64 Mbps/104.45 Kpps, importance 2, managed_objects ("Tonga"), (parent managed object "nil")' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html