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

r"
"
gsim

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(192.168.1.\d{1,3}).*?((\w{2}[:]){5}(\w{2}))"; string input = @"{ ""34:d2:70:87:42:68;"": [ ""192.168.1.81"", ""\""amazon-8dee0891a\"";"" ], ""98:e0:d9:91:bc:71;"": [ ""192.168.1.32"", ""\""Cathys-Air\"";"" ], ""88:71:e5:b3:cb:4e;"": [ ""192.168.1.172"", ""\""amazon-205f4e28e\"";"" ], ""34:d2:70:7f:df:e7;"": [ ""192.168.1.76"", ""\""amazon-8b38e6c4e\"";"" ], ""88:71:e5:a2:ff:66;"": [ ""192.168.1.77"", ""\""amazon-43faa4ef3\"";"" ], ""b8:3e:59:f1:73:9f;"": [ ""192.168.1.190"", ""\""Roku"" ], ""18:b4:30:14:bc:da;"": [ ""192.168.1.179"", ""\""02AA01AC42140DKR\"";"" ], ""ac:d1:b8:4d:a3:85;"": [ ""192.168.1.180"", ""\""NPI4DA385\"";"" ], ""14:91:82:c9:8b:61;"": [ ""192.168.1.174"", ""\""wemo\"";"" ], ""14:91:82:00:d5:35;"": [ ""192.168.1.184"", ""\""wemo\"";"" ], ""08:00:27:89:03:db;"": ["; RegexOptions options = RegexOptions.Singleline | RegexOptions.IgnoreCase | 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