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 = @"request=""(?Flagt1>.*?)""(.*?\/(?<Flag2>.*?\?)(\g'1'))"; string input = @"Aug 25 03:07:19 localhost.localdomainASM:unit_hostname=""bigip1"",management_ip_address=""192.168.41.200"",management_ip_address_2=""N/A"",http_class_name=""/Common/log_to_elk_policy"",web_application_name=""/Common/log_to_elk_policy"",policy_name=""/Common/log_to_elk_policy"",policy_apply_date=""2020-08-10 06:50:39"",violations=""HTTP protocol compliance failed"",support_id=""5666478231990524056"",request_status=""blocked"",response_code=""0"",ip_client=""10.43.0.86"",route_domain=""0"",method=""GET"",protocol=""HTTP"",query_string=""name='"",x_forwarded_for_header_value=""N/A"",sig_ids=""N/A"",sig_names=""N/A"",date_time=""2020-08-25 03:07:19"",severity=""Eror"",attack_type=""Non-browser Client,HTTP Parser Attack"",geo_location=""N/A"",ip_address_intelligence=""N/A"",username=""N/A"",session_id=""0"",src_port=""39348"",dest_port=""80"",dest_ip=""10.43.0.201"",sub_violations=""HTTP protocol compliance failed:Bad HTTP version"",virus_name=""N/A"",violation_rating=""5"",websocket_direction=""N/A"",websocket_message_type=""N/A"",device_id=""N/A"",staged_sig_ids="",staged_sig_names="",threat_campaign_names=""N/A"",staged_threat_campaign_names=""N/A"",blocking_exception_reason=""N/A"",captcha_result=""not_received"",microservice=""N/A"",tap_event_id=""N/A"",tap_vid=""N/A"",vs_name=""/Common/adv_waf_vs"",sig_cves=""N/A"",staged_sig_cves=""N/A"",uri=""/random"",fragment="",request=""GET /random?name=' or 1 = 1' HTTP/1.1\r\n"",response=""Response logging disabled"""; 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