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 = @"\""num_records\\"":\s*(\d+)"; string input = @"""{\""cursor\"":\""\"",\""hits\"":3,\""results\"":[{\""id\"":65673,\""num_records\"":14631,\""assets\"":{\""ip_addresses\"":14631,\""password\"":14631,\""target_url\"":14631,\""keyboard_languages\"":14631,\""user_sys_registered_owner\"":14484,\""country\"":14631,\""infected_machine_id\"":14631,\""email\"":7346,\""username\"":7285,\""user_os\"":14631,\""user_hostname\"":14631,\""log_id\"":14631,\""infected_time\"":14631,\""country_code\"":14581}},{\""id\"":65675,\""num_records\"":2602,\""assets\"":{\""display_resolution\"":2602,\""ip_addresses\"":2534,\""user_browser\"":2602,\""password\"":2602,\""target_url\"":2602,\""keyboard_languages\"":2602,\""user_sys_registered_owner\"":2601,\""country\"":2597,\""infected_machine_id\"":2602,\""email\"":943,\""full_name\"":25,\""av_softwares\"":2348,\""username\"":1659,\""infected_path\"":2534,\""user_os\"":2602,\""log_id\"":2602,\""infected_time\"":2602,\""country_code\"":2597,\""timezone\"":2602}},{\""id\"":65677,\""num_records\"":139,\""assets\"":{\""display_resolution\"":139,\""ip_addresses\"":139,\""user_browser\"":139,\""password\"":139,\""target_url\"":139,\""keyboard_languages\"":139,\""user_sys_registered_owner\"":139,\""country\"":139,\""infected_machine_id\"":139,\""email\"":3,\""full_name\"":7,\""av_softwares\"":139,\""username\"":136,\""infected_path\"":139,\""user_os\"":139,\""log_id\"":139,\""infected_time\"":139,\""country_code\"":139,\""timezone\"":139}}]}"" "; 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