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 = @"^(?P<alb_type>(https?|h2|wss?))\s*(?P<alb_timestamp>[^\s]+)\s*(?P<alb_elb>[^\s]+)\s*(?P<alb_client_addr>[^:]+):\s*(?P<alb_client_port>[^\s]+)\s*(?P<alb_target_addr>[^:]+):(?P<alb_target_port>[^\s]+)\s*(?P<alb_request_processing_time>[^\s]+)\s*(?P<alb_target_processing_time>[^\s]+)\s*(?P<alb_response_processing_time>[^\s]+)\s*(?P<alb_elb_status_code>[^\s]+)\s*(?P<alb_target_status_code>[^\s]+)\s*(?P<alb_received_bytes>[^\s]+)\s*(?P<alb_sent_bytes>[^\s]+)\s*""(?P<alb_request>.*?)""\s+""(?P<alb_user_agent>[^\""]+)""\s*(?P<alb_ssl_cipher>[^\s]+)\s*(?P<alb_ssl_protocol>[^\s]+)\s*(?P<alb_target_group_arn>[^\s]+)\s*""(?P<alb_trace_id>[^\""]+)""\s*""(?P<alb_domain_name>[a-zA-Z0-9\.\-:]+)""\s*""(?P<alb_chosen_cert_arn>[^\""]+)""\s*(?P<alb_matched_rule_priority>[^\s]+)\s*(?P<alb_request_creation_time>[^\s]+)\s*\s*""(?P<alb_actions_executed>[^\s]+)""\s*""(?P<alb_redirect_url>[^\s]+)""\s*""(?P<alb_error_reason>[^\""]+)""\s*""?(?P<alb_target_port_list>[0-9 :\.-]+)""?\s*""?(?P<alb_target_status_code_list>[0-9 -]+)""?"; string input = @"http 2018-07-02T22:23:00.186641Z app/my-loadbalancer/50dc6c495c0c9188 192.168.131.39:2817 10.0.0.1:80 0.000 0.001 0.000 200 200 34 366 ""GET http://www.example.com:80/ HTTP/1.1"" ""curl/7.46.0"" - - arn:aws:elasticloadbalancing:us-east-2:123456789012:targetgroup/my-targets/73e2d6bc24d8a067 ""Root=1-58337262-36d228ad5d99923122bbe354"" ""-"" ""-"" 0 2018-07-02T22:22:48.364000Z ""forward"" ""-"" ""-"" 80 200 ws 2018-07-02T22:23:00.186641Z app/my-loadbalancer/50dc6c495c0c9188 10.0.0.140:40914 10.0.1.192:8010 0.001 0.003 0.000 101 101 218 587 ""GET http://10.0.0.30:80/ HTTP/1.1"" ""-"" - - arn:aws:elasticloadbalancing:us-east-2:123456789012:targetgroup/my-targets/73e2d6bc24d8a067 ""Root=1-58337364-23a8c76965a2ef7629b185e3"" ""-"" ""-"" 1 2018-07-02T22:22:48.364000Z ""forward"" ""-"" ""-"" 80 200 wss 2018-07-02T22:23:00.186641Z app/my-loadbalancer/50dc6c495c0c9188 10.0.0.140:44244 10.0.0.171:8010 0.000 0.001 0.000 101 101 218 786 ""GET https://10.0.0.30:443/ HTTP/1.1"" ""-"" ECDHE-RSA-AES128-GCM-SHA256 TLSv1.2 arn:aws:elasticloadbalancing:us-west-2:123456789012:targetgroup/my-targets/73e2d6bc24d8a067 ""Root=1-58337364-23a8c76965a2ef7629b185e3"" ""-"" ""-"" 1 2018-07-02T22:22:48.364000Z ""forward"" ""-"" ""-"" ""44244"" ""101"" "; 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