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
Processing...

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"errorDescription\""\:\""(?<errorDescription>[^\""]+).+errorCode\""\:\""(?<errorCode>[^\""]+)"; string input = @"2016-10-25 12:33:31,926 [http-00000:13111-2] INFO [org.apache.cxf.interceptor.LoggingInInterceptor ?] Inbound Message ---------------------------- ID: 18 Response-Code: 200 Encoding: UTF-8 Content-Type: application/json;charset=UTF-8 Headers: {content-type=[application/json;charset=UTF-8], Date=[Tue, 25 Oct 2016 17:33:30 GMT], Expires=[Thu, 01 Jan 1970 00:00:00 GMT], Set-Cookie=[BrowserId=L8p9Eij0T4Sfp-INSP9zDw;Path=/;Domain=.salesforce;Expires=Sat, 24-Dec-2016 17:33:30 GMT], transfer-encoding=[chunked]} Payload: {""responseCode"":""201"",""messageId"":""704c8163-13d4-42b8-a684-94b9d23e849e"", ""lead"":[{""responseCode"":""201"",""leadID"":null,""errors"":[{""errorField"":""head"",""errorDescription"":""The value of email is invalid."",""errorCode"":""Value_Invalid_E400""},{""errorField"":""bestTimeToContact"",""errorDescription"":""The value of bestTimeToContact is invalid."",""errorCode"":""Value_Invalid_E400""}]}]} ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 2016-10-25 12:33:31,986 [http-000000:13111-2] INFO [org.apache.cxf.interceptor.LoggingOutInterceptor ?] Outbound Message --------------------------- ID: 17 Response-Code: 200 Content-Type: application/json Headers: {Content-Type=[application/json], Date=[Tue, 25 Oct 2016 17:33:31 GMT]} Payload: {""errors"":[{""errorCode"":""Value_Invalid_E400"",""errorDescription"":""The value of email is invalid."",""errorField"":""head""},{""errorCode"":""Value_Invalid_E400"",""errorDescription"":""The value of bestTimeToContact is invalid."",""errorField"":""bestTimeToContact""}]} --------------------------------------"; 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