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<date>[^\s]+)\s+(?P<time>[^\s]+)\s+(?P<time_taken>[^\s]+)\s+(?P<c_ip>[^\s]+)\s+(?P<cs_username>[^\s]+)\s+(?P<cs_auth_group>[^\s]+)\s+(?P<x_exception_id>[^\s]+)\s+(?P<filter_result>[^\s]+).*?\""(?P<category>[^\""]+)\""\s+(?P<http_referrer>[^\s]+)\s+(?P<sc_status>[^\s]+)\s+(?P<action>[^\s]+)\s+(?P<cs_method>[^\s]+)\s+(?P<http_content_type>[^\s]+)\s+(?P<cs_uri_scheme>[^\s]+)\s+(?P<cs_host>[^\s]+)\s+(?P<cs_uri_port>[^\s]+)\s+(?P<cs_uri_path>[^\s]+)\s+(?P<cs_uri_query>[^\s]+)\s+(?P<cs_uri_extension>[^\s]+)\s+\""(?P<http_user_agent>[^\""]+)\""\s+(?P<s_ip>[^\s]+)\s+(?P<sc_bytes>[^\s]+)\s+(?P<cs_bytes>[^\s]+)\s+\""?(?P<x_virus_id>[^\""]+)\""?\s+\""(?P<x_bluecoat_application_name>[^\""]+)\""\s+\""(?P<x_bluecoat_application_operation>[^\""]+)\"""; string input = @" 2015-11-05 16:01:53 54 10.0.19.44 hammlx1 - - OBSERVED ""Web Ads/Analytics"" http://bcp.crwdcntrl.net/5/c=1226/rand=328960996/pv=y/int=%23OpR%2358075%23DailyMail%20%3A%20Time%20of%20Day%20%3A%2010AM%C2%A0/int=%23OpR%2358689%23Dailymail%20%3A%20Weather-current-description%20%3A%20Cloudy%20with%20outbreaks%20of%20Rain/int=%23OpR%2358690%23Dailymail%20%3A%20Weather-current-temperature%20%3A%2043%C2%B0F/int=%23OpR%2358691%23Dailymail%20%3A%20Weather-upcoming-description%20%3A%20Scattered%20Showers/int=%23OpR%2358692%23Dailymail%20%3A%20Weather-upcoming-temperature%20%3A%2046%C2%B0F/med=%23OpR%2350629%23DailyMail%20%3A%20Home%20Page%20Date%20%3A%20Thursday%2C%20Nov%205th%202015/seg=%23OpR%2350561%23Date%20%3A%20Thursday%2C%20Nov%205th%202015/ug=%23OpR%2350557%23GrapeShot%20%3A%20Channel%20%3A%20gv_weightwatchers/ug=%23OpR%2350558%23GrapeShot%20%3A%20Channel%20%3A%20gv_weightwatchers/ug=%23OpR%2350559%23GrapeShot%20%3A%20US%20Channel%20%3A%20us_negative_crime/ug=%23OpR%2350560%23GrapeShot%20%3A%20US%20Channel%20%3A%20us_negative_crime/genp=%23OpR%2330426%23Site%20Section%20%3A%20index/genp=%23OpR%2330427%23Site%20Section%20%3A%20ushome/rt=ifr 204 TCP_NC_MISS GET image/png;charset=UTF-8 http su.addthis.com 80 /red/usync ?pid=11127&puid=ce5754badf674f9ba73d138adc3e8e1a - ""Mozilla/5.0 (Windows NT 6.1; WOW64; Trident/7.0; rv:11.0) like Gecko"" 10.0.2.248 451 2394 - ""none"" ""none"" 2015-11-05 16:05:14 763 10.80.64.129 cajones - us-ads.openx.net 173.241.244.221 None - - PROXIED ""Web Ads/Analytics"" http://lagrangenews.com/news/5895/students-strive-to-serve 200 TCP_NC_MISS GET application/json http us-ads.openx.net 80 /w/1.0/acj ?o=5040266117&callback=OX_5040266117&ju=http%3A//lagrangenews.com/news/5895/students-strive-to-serve&jr=http%3A//lagrangenews.com/&auid=538038002&dims=1419x731&adxy=0%2C0&res=1440x900x32&plg=pm&ch=utf-8&tz=300&ws=1419x731&ifr=0&tws=1419x731&vmt=1&bi=66daec33-f482-4821-b52e-7f07e884dfe3&sd=29 - ""Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET4.0C; .NET4.0E; Media Center PC 6.0; BRI/2)"" 10.75.95.91 1906 2550 - ""none"" ""none"" none"; 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