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 = @"web\.\d{1,}\s+\|\s+(\{|>)"; string input = @"10:50:46 AM web.2 | > creating redis session"",""time"":""2016-05-18T17:50:46.161Z"",""v"":0} 10:50:46 AM web.3 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28296,""level"":20,""middleware"":""cache-headers"",""msg"":""Loading middleware:: cache-headers"",""time"":""2016-05-18T17:50:46.172Z"",""v"":0} 10:50:46 AM web.2 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28283,""level"":40,""msg"":""LC-SESSION: set the secret for the session cookies in the config file, check lc-session config"",""time"":""2016-05-18T17:50:46.174Z"",""v"":0} 10:50:46 AM web.3 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28296,""level"":20,""middleware"":""client-id"",""msg"":""Loading middleware:: client-id"",""time"":""2016-05-18T17:50:46.175Z"",""v"":0} 10:50:46 AM web.3 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28296,""level"":20,""middleware"":""cookie-parser"",""msg"":""Loading middleware:: cookie-parser"",""time"":""2016-05-18T17:50:46.175Z"",""v"":0} 10:50:46 AM web.3 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28296,""level"":20,""middleware"":""guid"",""msg"":""Loading middleware:: guid"",""time"":""2016-05-18T17:50:46.175Z"",""v"":0} 10:50:46 AM web.3 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28296,""level"":20,""middleware"":""healthy"",""msg"":""Loading middleware:: healthy"",""time"":""2016-05-18T17:50:46.176Z"",""v"":0} 10:50:46 AM web.2 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28283,""level"":20,""middleware"":""sso"",""msg"":""Loading middleware:: sso"",""time"":""2016-05-18T17:50:46.177Z"",""v"":0} 10:50:46 AM web.2 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28283,""level"":30,""msg"":""SSO-MIDDLEWARE: Detecting SSO config"",""time"":""2016-05-18T17:50:46.177Z"",""v"":0} 10:50:46 AM web.2 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28283,""level"":30,""msg"":""SSO-MIDDLEWARE: enabling JANUS-SSO"",""time"":""2016-05-18T17:50:46.179Z"",""v"":0} 10:50:46 AM web.2 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28283,""level"":20,""middleware"":""timer"",""msg"":""Loading middleware:: timer"",""time"":""2016-05-18T17:50:46.180Z"",""v"":0} 10:50:46 AM web.1 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28278,""level"":20,""middleware"":""cache-headers"",""msg"":""Loading middleware:: cache-headers"",""time"":""2016-05-18T17:50:46.180Z"",""v"":0} 10:50:46 AM web.2 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28283,""level"":20,""middleware"":""setTrackingData"",""msg"":""Loading middleware:: setTrackingData"",""time"":""2016-05-18T17:50:46.181Z"",""v"":0} 10:50:46 AM web.1 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28278,""level"":20,""middleware"":""client-id"",""msg"":""Loading middleware:: client-id"",""time"":""2016-05-18T17:50:46.181Z"",""v"":0} 10:50:46 AM web.1 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28278,""level"":20,""middleware"":""cookie-parser"",""msg"":""Loading middleware:: cookie-parser"",""time"":""2016-05-18T17:50:46.181Z"",""v"":0} 10:50:46 AM web.1 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28278,""level"":20,""middleware"":""guid"",""msg"":""Loading middleware:: guid"",""time"":""2016-05-18T17:50:46.181Z"",""v"":0} 10:50:42 AM haproxy.1 | [WARNING] 138/105042 (28265) : Server nodes/node5001 is DOWN, reason: Layer4 connection problem, info: ""Connection refused"", check duration: 0ms. 2 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue. 10:50:42 AM web.1 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.1 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:42 AM web.2 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.2 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:42 AM web.3 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.3 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:42 AM haproxy.1 | [WARNING] 138/105042 (28265) : Server nodes/node5002 is DOWN, reason: Layer4 connection problem, info: ""Connection refused"", check duration: 0ms. 1 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue. 10:50:42 AM web.4 | warn: --minUptime not set. Defaulting to: 1000ms 10:50:42 AM web.4 | warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms 10:50:43 AM haproxy.1 | [WARNING] 138/105043 (28265) : Server nodes/node5003 is DOWN, reason: Layer4 connection problem, info: ""Connection refused"", check duration: 0ms. 0 active and 0 backup servers left. 0 sessions active, 0 requeued, 0 remaining in queue. 10:50:43 AM haproxy.1 | [ALERT] 138/105043 (28265) : backend 'nodes' has no server available! 10:50:43 AM web.2 | {""name"":""investor-webapp-registration"",""hostname"":""lasinvonboard101-prod.tlcinternal.com"",""pid"":28283,""level"":30,""msg"":""starting server on port 5001"",""time"":""2016-05-18T17:50:43.751Z"",""v"":0}"; 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