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 = @"{""time"": ""([^""]+)"", ""remote_addr"": ""([^""]+)"", ""x_forward_for"": ""([^""]+)"", ""request_id"": ""([^""]+)"", ""remote_user"": ""([^""]+)"", ""bytes_sent"": (\d+), ""request_time"": ([\d.]+), ""status"": (\d+), ""vhost"": ""([^""]+)"", ""request_proto"": ""([^""]+)"", ""path"": ""([^""]+)"", ""request_query"": ""([^""]+)"", ""request_length"": (\d+), ""duration"": ([\d.]+),""method"": ""([^""]+)"", ""http_referrer"": ""([^""]+)"", ""http_user_agent"": ""([^""]+)"", ""proxy_upstream_name"": ""([^""]+)"", ""service_name"": ""([^""]+)""}"; string input = @"{""time"": ""2023-09-02T13:06:07+00:00"", ""remote_addr"": ""127.0.0.6"", ""x_forward_for"": ""127.0.0.6"", ""request_id"": ""08aaccca-f6e7-4480-9f7b-d157f1dce306"", ""remote_user"": ""-"", ""bytes_sent"": 277, ""request_time"": 0.386, ""status"": 200, ""vhost"": ""10.160.96.120"", ""request_proto"": ""HTTP/1.1"", ""path"": ""/savethesale/v1/validateemployee/243060/couponmgmt"", ""request_query"": ""-"", ""request_length"": 423, ""duration"": 0.384,""method"": ""GET"", ""http_referrer"": ""-"", ""http_user_agent"": ""PostmanRuntime/7.32.3"", ""proxy_upstream_name"": ""ns-sell-save-the-sale-9097"", ""service_name"": ""save-the-sale""}"; 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