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 = @"""repoType"":(.*?)""repo"":(.*?),|""resType"":(.*?),|""result"":(.*?),|""policy"":(.*?),|""enforcer"":(.*?),|""sess"":(.*?),|""cliType"":(.*?),|""reqData"":(.*?),|""agentHost"":(.*?),|""logType"":(.*?),|""id"":(.*?),|""seq_num"":(.*?),|""event_count"":(.*?),|""event_dur_ms"":(.*?),|""tags"":(.*?),|""additional_info"":|""{(.)(?!$)"; string input = @"{""repoType"":3,""repo"":""DEV01_hive"",""reqUser"":""na230292"",""evtTime"":""2018-05-07 07:29:16.765"",""access"":""ALTER"",""resource"":""stg_hr_erp_hr_erpprod/hr_dm_application_groups"",""resType"":""@table"",""action"":""alter"",""result"":1,""policy"":695,""enforcer"":""ranger-acl"",""sess"":""ce536988-846d-47d2-a9dc-40e88c9c3e1a"",""cliType"":""HIVESERVER2"",""cliIP"":""149.25.76.150"",""reqData"":""msck repair table stg_hr_erp_hr_erpprod.hr_dm_application_groups"",""agentHost"":""rpc11743.corp.ncr.com"",""logType"":""RangerAudit"",""id"":""358f75d9-8423-49e1-bd3e-3cc795cccf2e-25620"",""seq_num"":51241,""event_count"":1,""event_dur_ms"":0,""tags"":[blah],""additional_info"":""{\""remote-ip-address\"":149.25.76.150, \""forwarded-ip-addresses\"":[]"",""cluster_name"":""DEV01""} "; 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