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 = @"{""pm10"":\s+(\d+(\.\d+)?)[^}]*}]"; string input = @"[{""pm10"": 10.1, ""pm25"": 4.7, ""time"": ""15.11.2019 13:01:49""}, {""pm25"": 4.5, ""pm10"": 11.2, ""time"": ""15.11.2019 13:07:21""}, {""pm10"": 10.1, ""pm25"": 4.5, ""time"": ""15.11.2019 13:12:54""}, {""pm25"": 4.3, ""pm10"": 8.7, ""time"": ""15.11.2019 13:18:26""}, {""pm10"": 12.3, ""pm25"": 5.0, ""time"": ""15.11.2019 13:23:58""}, {""pm25"": 4.8, ""pm10"": 9.9, ""time"": ""15.11.2019 13:29:31""}, {""pm10"": 9.7, ""pm25"": 4.4, ""time"": ""15.11.2019 13:35:03""}, {""pm25"": 4.5, ""pm10"": 9.8, ""time"": ""15.11.2019 13:40:35""}, {""pm10"": 9.1, ""pm25"": 5.0, ""time"": ""15.11.2019 13:46:08""}, {""pm25"": 4.7, ""pm10"": 10.8, ""time"": ""15.11.2019 13:51:40""}, {""pm10"": 9.6, ""pm25"": 4.5, ""time"": ""15.11.2019 13:57:13""}, {""pm25"": 4.8, ""pm10"": 10.2, ""time"": ""15.11.2019 14:02:45""}, {""pm10"": 12.0, ""pm25"": 5.0, ""time"": ""15.11.2019 14:08:17""}, {""pm25"": 5.0, ""pm10"": 11.0, ""time"": ""15.11.2019 14:13:50""}, {""pm10"": 11.9, ""pm25"": 4.6, ""time"": ""15.11.2019 14:19:22""}, {""pm25"": 5.3, ""pm10"": 11.1, ""time"": ""15.11.2019 14:24:54""}, {""pm10"": 12.5, ""pm25"": 4.8, ""time"": ""15.11.2019 14:30:27""}, {""pm25"": 5.7, ""pm10"": 12.9, ""time"": ""15.11.2019 14:35:59""}, {""pm10"": 10.7, ""pm25"": 5.1, ""time"": ""15.11.2019 14:41:32""}, {""pm25"": 5.4, ""pm10"": 13.8, ""time"": ""15.11.2019 14:47:04""}, {""pm10"": 12.6, ""pm25"": 5.7, ""time"": ""15.11.2019 14:52:36""}, {""pm25"": 6.2, ""pm10"": 14.2, ""time"": ""15.11.2019 15:10:09""}, {""pm10"": 13.7, ""pm25"": 6.0, ""time"": ""15.11.2019 15:15:41""}, {""pm25"": 7.0, ""pm10"": 15.6, ""time"": ""15.11.2019 15:16:58""}, {""pm10"": 15.2, ""pm25"": 7.2, ""time"": ""15.11.2019 15:22:28""}, {""pm25"": 7.0, ""pm10"": 15.8, ""time"": ""15.11.2019 16:51:10""}, {""pm10"": 14.2, ""pm25"": 6.7, ""time"": ""15.11.2019 16:56:42""}, {""pm25"": 7.7, ""pm10"": 17.2, ""time"": ""15.11.2019 16:58:32""}, {""pm10"": 16.2, ""pm25"": 6.6, ""time"": ""15.11.2019 17:04:04""}, {""pm25"": 7.3, ""pm10"": 16.4, ""time"": ""15.11.2019 17:09:37""}, {""pm10"": 15.6, ""pm25"": 6.9, ""time"": ""15.11.2019 17:15:09""}, {""pm25"": 6.6, ""pm10"": 14.7, ""time"": ""15.11.2019 17:20:42""}, {""pm10"": 14.9, ""pm25"": 6.5, ""time"": ""15.11.2019 17:26:14""}, {""pm25"": 6.8, ""pm10"": 14.8, ""time"": ""15.11.2019 17:31:46""}, {""pm10"": 13.7, ""pm25"": 6.4, ""time"": ""15.11.2019 17:37:19""}, {""pm25"": 7.1, ""pm10"": 16.0, ""time"": ""15.11.2019 17:50:58""}, {""pm10"": 15.0, ""pm25"": 6.8, ""time"": ""15.11.2019 17:52:08""}, {""pm25"": 7.2, ""pm10"": 16.0, ""time"": ""15.11.2019 17:57:40""}, {""pm10"": 15.7, ""pm25"": 7.1, ""time"": ""15.11.2019 18:03:13""}, {""pm25"": 6.9, ""pm10"": 14.9, ""time"": ""15.11.2019 18:08:45""}, {""pm10"": 18.6, ""pm25"": 7.4, ""time"": ""15.11.2019 18:14:17""}, {""pm25"": 8.0, ""pm10"": 18.6, ""time"": ""15.11.2019 18:19:50""}, {""pm10"": 19.3, ""pm25"": 7.9, ""time"": ""15.11.2019 18:25:22""}, {""pm25"": 8.2, ""pm10"": 19.8, ""time"": ""15.11.2019 18:30:54""}, {""pm10"": 17.5, ""pm25"": 8.0, ""time"": ""15.11.2019 18:36:27""}, {""pm25"": 7.6, ""pm10"": 16.4, ""time"": ""15.11.2019 18:41:59""}, {""pm10"": 16.7, ""pm25"": 7.9, ""time"": ""15.11.2019 18:47:31""}, {""pm25"": 7.4, ""pm10"": 16.8, ""time"": ""15.11.2019 18:53:04""}, {""pm10"": 17.6, ""pm25"": 7.4, ""time"": ""15.11.2019 18:58:36""}, {""pm25"": 7.2, ""pm10"": 20.3, ""time"": ""15.11.2019 19:04:09""}, {""pm10"": 17.3, ""pm25"": 7.3, ""time"": ""15.11.2019 19:09:41""}, {""pm25"": 8.5, ""pm10"": 18.3, ""time"": ""15.11.2019 19:15:13""}, {""pm10"": 20.2, ""pm25"": 8.8, ""time"": ""15.11.2019 19:20:46""}, {""pm25"": 9.0, ""pm10"": 21.4, ""time"": ""15.11.2019 19:26:18""}, {""pm10"": 20.7, ""pm25"": 9.3, ""time"": ""15.11.2019 19:31:50""}, {""pm25"": 8.5, ""pm10"": 17.0, ""time"": ""15.11.2019 19:37:23""}, {""pm10"": 18.1, ""pm25"": 8.2, ""time"": ""15.11.2019 19:42:55""}, {""pm25"": 7.9, ""pm10"": 17.9, ""time"": ""15.11.2019 19:48:28""}, {""pm10"": 16.4, ""pm25"": 7.7, ""time"": ""15.11.2019 19:54:00""}, {""pm25"": 8.0, ""pm10"": 16.6, ""time"": ""15.11.2019 19:59:32""}, {""pm10"": 15.7, ""pm25"": 7.9, ""time"": ""15.11.2019 20:05:05""}, {""pm25"": 7.0, ""pm10"": 15.0, ""time"": ""15.11.2019 20:10:37""}, {""pm10"": 14.6, ""pm25"": 6.7, ""time"": ""15.11.2019 20:16:09""}, {""pm25"": 7.1, ""pm10"": 12.7, ""time"": ""15.11.2019 20:21:42""}, {""pm10"": 16.6, ""pm25"": 7.3, ""time"": ""15.11.2019 20:27:14""}, {""pm25"": 6.4, ""pm10"": 14.0, ""time"": ""15.11.2019 20:32:47""}, {""pm10"": 15.2, ""pm25"": 6.7, ""time"": ""15.11.2019 20:38:19""}, {""pm25"": 6.8, ""pm10"": 12.8, ""time"": ""15.11.2019 20:43:51""}, {""pm10"": 12.7, ""pm25"": 6.6, ""time"": ""15.11.2019 20:49:24""}, {""pm25"": 6.9, ""pm10"": 12.2, ""time"": ""15.11.2019 20:54:56""}, {""pm10"": 11.2, ""pm25"": 6.4, ""time"": ""15.11.2019 21:00:28""}, {""pm25"": 5.6, ""pm10"": 11.5, ""time"": ""15.11.2019 21:06:01""}, {""pm10"": 11.2, ""pm25"": 5.6, ""time"": ""15.11.2019 21:11:33""}, {""pm25"": 2.4, ""pm10"": 5.2, ""time"": ""16.11.2019 08:50:54""}, {""pm10"": 5.2, ""pm25"": 2.3, ""time"": ""16.11.2019 08:56:27""}, {""pm25"": 2.7, ""pm10"": 8.2, ""time"": ""16.11.2019 09:01:59""}, {""pm10"": 4.7, ""pm25"": 2.1, ""time"": ""16.11.2019 09:07:32""}, {""pm25"": 2.0, ""pm10"": 5.1, ""time"": ""16.11.2019 09:13:04""}, {""pm10"": 4.6, ""pm25"": 2.1, ""time"": ""16.11.2019 09:18:36""}, {""pm25"": 5.0, ""pm10"": 11.7, ""time"": ""16.11.2019 13:16:41""}, {""pm10"": 10.1, ""pm25"": 4.6, ""time"": ""16.11.2019 13:22:11""}, {""pm25"": 7.3, ""pm10"": 17.2, ""time"": ""16.11.2019 15:36:53""}, {""pm10"": 13.6, ""pm25"": 6.2, ""time"": ""16.11.2019 15:42:25""}, {""pm25"": 7.7, ""pm10"": 15.4, ""time"": ""16.11.2019 17:02:49""}, {""pm10"": 14.5, ""pm25"": 7.1, ""time"": ""16.11.2019 17:08:22""}, {""pm25"": 8.5, ""pm10"": 15.7, ""time"": ""16.11.2019 17:38:24""}, {""pm10"": 15.2, ""pm25"": 7.8, ""time"": ""16.11.2019 17:43:57""}, {""pm25"": 8.2, ""pm10"": 19.6, ""time"": ""16.11.2019 17:49:29""}, {""pm10"": 16.5, ""pm25"": 7.7, ""time"": ""16.11.2019 17:55:01""}, {""pm25"": 8.1, ""pm10"": 13.4, ""time"": ""16.11.2019 20:46:43""}, {""pm10"": 14.4, ""pm25"": 8.4, ""time"": ""16.11.2019 20:52:15""}, {""pm25"": 7.2, ""pm10"": 14.3, ""time"": ""16.11.2019 20:57:48""}, {""pm10"": 12.7, ""pm25"": 7.4, ""time"": ""16.11.2019 21:03:20""}, {""pm25"": 7.0, ""pm10"": 11.1, ""time"": ""16.11.2019 21:08:52""}, {""pm10"": 11.4, ""pm25"": 6.4, ""time"": ""16.11.2019 21:14:25""}, {""pm25"": 6.1, ""pm10"": 9.2, ""time"": ""16.11.2019 21:38:13""}, {""pm10"": 10.7, ""pm25"": 6.0, ""time"": ""16.11.2019 21:43:45""}, {""pm25"": 6.4, ""pm10"": 10.0, ""time"": ""16.11.2019 21:49:18""}, {""pm10"": 9.7, ""pm25"": 6.1, ""time"": ""16.11.2019 21:54:50""}, {""pm25"": 5.9, ""pm10"": 8.2, ""time"": ""16.11.2019 22:00:22""}, {""pm10"": 9.5, ""pm25"": 6.3, ""time"": ""16.11.2019 22:05:55""}]"; 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