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]
  • Character class intersection
    [\w&&[^\d]]
  • 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 = @"(?<_filename_>.*?):(?<line>\d+)(?:[:](?<column>\d+)(?:[:](?<endLine>\d+):(?<endColumn>\d+))?)?: (?<type>\w+): (?<message>.*)\r?(\n|$)"; string input = @"# --show-error-end src/waybar_check_gmail/config/config.py:19:17:19:17: error: Dict entry 0 has incompatible type ""str"": ""None""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:20:17:20:17: error: Dict entry 1 has incompatible type ""str"": ""None""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:21:17:21:17: error: Dict entry 2 has incompatible type ""str"": ""None""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:26:17:26:17: error: Dict entry 1 has incompatible type ""str"": ""bool""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:27:17:27:17: error: Dict entry 2 has incompatible type ""str"": ""bool""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:28:17:28:17: error: Dict entry 3 has incompatible type ""str"": ""bool""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:29:17:29:17: error: Dict entry 4 has incompatible type ""str"": ""None""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:30:17:30:17: error: Dict entry 5 has incompatible type ""str"": ""bool""; expected ""str"": ""str"" [dict-item] # WITHOUT --show-error-end, ONLY: --show-column-numbers [info] src/waybar_check_gmail/config/config.py:19:17: error: Dict entry 0 has incompatible type ""str"": ""None""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:20:17: error: Dict entry 1 has incompatible type ""str"": ""None""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:21:17: error: Dict entry 2 has incompatible type ""str"": ""None""; expected ""str"": ""str"" [dict-item] src/waybar_check_gmail/config/config.py:26:17: error: Dict entry 1 has incompatible type ""str"": ""bool""; expected ""str"": ""str"" [dict-item]"; 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