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

/
/

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"flavor=\""[^\""]+\(([^\)]+)"; string input = @"<182>1 2016-08-30T13:11:17.530157+02:00 cloudcapprorh01.boaweng.gsnetcloud.corp capacity.instances - - [timeQuality tzKnown=""1"" isSynced=""1"" syncAccuracy=""946892""] diskconfig=""MANUAL"" availability_zone=""BOAW-1"" host=""srvboaw01cnodep38.boaw-infra.gsnetcloud.corp"" hypervisor_hostname=""srvboaw01cnodep38.boaw-infra.gsnetcloud.corp"" instance_name=""inst-00001ff5"" power_state=""1"" task_state=""None"" vm_state=""active"" launched_at=""2015-07-23T07:18:03.000000"" terminated_at=""None"" accessipv4="" accessipv6="" addresses=""PRB_PRODSERV_LAB (Template 0) \ Subnet 0=10.200.0.16"" config_drive="" created=""2015-07-23T07:17:59Z"" flavor=""sabor554??(adf) (1003)"" hostid=""76651d2e4c981ab8084dad155e52129580ed9fd4baf5fa628cd8bae8"" id=""61626999-026e-4d06-9eaa-835c0262b939"" image=""RHEL 7.0 (3fa495a8-fbb6-45c0-9c44-874b9016d4a3)"" key_name=""jdelarco"" name=""gitlab"" volumes_attached=""[]"" progress=""0"" project_id=""6e58b12be4bb4972bfb42812ee806065"" properties="" security_groups=""[{u'name': u'default'}]"" status=""ACTIVE"" updated=""2015-11-16T17:06:38Z"" user_id=""x100183"" region=BOAW"; Match m = Regex.Match(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