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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\""(?<my_field1>xyz-[^\""]*)\"":\""(?<my_field2>[^\""]*)"; string input = @" 2017-06-27 14:35:38.000 INFO [http-nio-0.0.0.0-19752-exec-4 - RequestResponseLoggerFilter] SessionID 2017-06-28-10:31:01-0855306 correlationID:bbacfa29-095d-49c0-b146-fe456h417ecbb681 ""Request"" : {""top"":{""ref"":""https://abc.com"",""adrum"":""isAjax:true"",""content-length"":""199"",""xyz-id"":""123456"",""origin"":""https://offline.xyz.com"",""xyz-authenticationprovider"":""kbc"",""xyz-kbc-entry"":""ipad"",""xyz-originaluri"":""/kpi/abcf"",""via"":""http/1.1 xyz.com"",""xyz-hyt-entrydomain"":""mb"",""xyz-ipaddress"":""117.00.109.103"",""xyz-originatorauthentication"":""VUJTLdGhlbnRpY2F0aW9uTW5hbFVyaT0lMkZhcGklMkZ3bWElMkZjcmVkaXQtY2FyZC1wYXltZW50cyUyRnYxJTJGc2NoZWR1bGVkJTJGYWRkJlVCUy1SZXF1ZXN0QmFzZVVybD1odHRwcyU"",""x-forwarded-host"":""offline.xyz.com"",""xyz-isuseraccessinganyaddressinternally"":""false"",""x-forwarded-prefix"":""/api"",""xyz-isuseraccessinginternally"":""false"",""host"":""offline.xyz.com"",""content-type"":""application/json"",""xyz-hyt-hashregistrationid"":""61fa7e9eb9afca3c09412a10fb02986d"",""accept-language"":""en-us"",""xyz-authenticationlevel"":""25"",""x-forwarded-proto"":""https"",""dnt"":""1"",""x-forwarded-for"":""173.66.169.203"",""xyz-requestbaseurl"":""https://offline.xyz.com/api"",""accept"":""*/*"",""xyz-hyt-registrationid"":""123456"",""x-forwarded-server"":""148.112.147.17"",""singularityheader"":""appId=7*ctrlguid=123456*acctguid=3f5d5ee2-41b3-4e59-ad10-de0b93044*ts=1498660534590*btid=2206*id=9497e8be-3275-417b-9893-30dbcca2d0*exitid=2*unresolvedexitid=164*cidfrom=148*etypeorder=CUSTOM*esubtype=CUSTOM*cidto=545"",""xyz-hyt-sessionid"":""2017-06-28-10:31:01-085"",""xyz-isproxyuser"":""false"",""xyz-isemployee"":""false"",""xyz-hyt-entrypoint"":""Mens"",""accept-encoding"":""gzip,deflate"",""user-agent"":""Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/603.2.5 (KHTML, like Gecko) Version/10.1.1 Safari/603.2.5"",""xyz-iscallersecure"":""true""},""correlationId"":""bbddfa29-09fd-45c0-b136-fe417ecbb681""}"; foreach (Match m in Regex.Matches(input, pattern)) { 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