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 = @"intensity\""\s*:\s*\(\""\w+\""\s*:\s*(?<intensity>\d+)"; string input = @"(""data"": [""from"" : ""2024-04-25T11: 30Z"", ""to"": ""2024-04-2512:00Z"", ""intensity"": (""forecast"": 152, ""actual"": null, ""index"": ""moderate""}), (""from"": ""2024-04-25T12:002"", ""intensity"": {""forecast"": 152, ""actual"": null, ""index"": ""moderate""}), (""from"": ""2024-04-25T12:30Z"", ""to"": {""from"": ""2024-04-25T13:00Z"", ""to"": ""2024-04-25T12: 30Z"", (""forecast"": 164, ""actual"": null, ""2024-04-2513: 30Z"", ""intensity"": (""forecast"": 154, ""to"": ""2024-04-25T13: 002"", ""intensity"": (""forecast"": 154, ""actual"": null, ""index"": ""actual"": null, ""index"": ""moderate""}), (""from"": ""2024-04-25T13:30Z*, ""to"": ""2024-04-25T14:002"", ""moderate""}}, ""intensity""： 04-25T14: 30Z"", ""to"" : ""index"": ""moderate""3}, (""from"": ""2024-04-25T14:002*, ""to"": ""2024-04-25T14:30Z"", ""intensity"": (""forecast"": 166, ""actual"": null, ""index"": ""moderate""}), (""from"": "" 2024-04-25T15:00Z"" ""actual"": nu11, ""index"" ""intensity"": {""forecast"": 170, ""actual"": null, ""index"": ""moderate""}), {""from"": ""2024-04-2515: 00Z"", 2024- ""to"" : ""moderate""}), {""from"": ""2024-04-25T15:30Z"", ""to"": ""2024-04-25T16:00Z"", ""intensity"": (""forecast"": 175, ""to"": ""2024-04-25T15: 30Z"", ""intensity"": {""forecast"": 172, ""2024-04-25T16: 30Z"", ""index"": ""moderate""}}, (""from"": ""2024-04-25T17:00Z"", ""to"": ""intensity"": (""forecast"": 177, ""actual"": null, ""index"": ""moderate""?), (""from"": ""2024-04-2516: 302"", ""actual"" : nu11, ""index"" ""moderate""}}, (""from"": ""2024-04-2516: 00Z"", ""to"": ""2024-04-25T17:002"", ""intensity"": (""forecast"": 179, ""actual"": null, 2024-04-2517: 30Z"", ""intensity"": (""forecast"": 181, ""actual"": null, 25T18:00Z"", ""intensity"": (""forecast"": 184, ""index"": ""moderate""}}, {""from"": ""2024-04-25T17: 30Z"", ""actual"": null, ""index"": ""moderate""}), (""from"": ""2024-04-25T18:002"", ""to"": ""2024-04-25T18: 30Z"", ""to"": ""2024-04- ""moderate""}}, (""from"": ""2024-04-2518: 30Z"", ""to"": ""2024-04-25T19:002"", ""intensity"": (""forecast"": 187, ""actual"": null, ""intensity"": (""forecast"": 190, ""actua1"": nul1, ""index"": ""index"": ""high""}}, (""from"": ""intensity"": {""forecast"": 193, ""actual"": null, ""index"": ""2024-04-25T19: 00Z"", ""to"": ""2024-04-25T19: 30Z"" ""high""}}, (""from"": ""2024-04-25T19:30Z"", ""to"": ""2024-04-25T20:00Z"", ""intensity"": {""forecast"": 194, ""2024-04-2520: 00Z"", ""to"": ""2024-04-25T20:30Z"", ""intensity"": {""forecast"": 195, ""actual"": null, ""index"": ""high""3}, (""from"": ""2024-04-25T20:30Z"", ""actual"": null, ""index"": ""high"")}, (""from"": ""2024-04-25T21:00Z"", ""intensity"": (""forecast"": 198, ""actual"": null, ""index"": ""high""'), (""from"": ""2024-04-25T21: 002"", ""2024-04-25T22: 00Z"", ""intensity"": {""forecast"": 187, ""actual"": null, ""to"": ""2024-04-25T21: 30Z"", ""intensity"": {""forecast"": 196, 'actual"": null, ""index"": ""high""}}, {""from"": ""2024-04-25T21:302"" ""to"" ""index"": ""moderate""}}, (""from"": ""2024-04-25T22:00Z"", ""to"": ""2024-04-25T22: 30Z"", ""intensity"": (""forecast"": 181, ""actual"": null, ""index"": ""moderate""}}, {""from"": ""2024-04-25T22:30Z"", ""to"": ""2024-04-25T23:002"", ""intensity"": (""forecast"": 180, ""actual"": null, ""index' moderate""｝｝，｛""from""： 25T23:30Z"", ""intensity"": {""forecast"": 172, ""actual"": null, ""index"": ""moderate""}}, {""from"": ""2024-04-25T23: 30Z"", ""2024-04-25T23:002"", ""to"": "" 2024-04- ""moderate""}}, {""from"": ""2024-04-26T00:00Z"", ""to"": ""2024-04-2600: 30Z"", ""intensity"": (""forecast"": 150, ""to"": ""2024-04-2600: 00Z"", ""intensity"": (""forecast"": 150, ""actual"": null, ""index"": ""actual"": null, ""index"": ""moderate"")}, (""from"": ""2024-04-26T00: 302"", ""to"": ""2024-04-26T01:00Z"" ""intensity"": {""forecast"": 149, ""actual"": null, ""index"": ""moderate""}}, (""from"": ""2024-04-26T01:002"", ""to"": ""2024-04-26T01:30Z"", ""intensity"": {""forecast"": 149, ""actual"": null, ""index"": ""moderate""}}, ..."; 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