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

/
/
gmi

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^((401178|401179|431274|438935|451416|457393|457631|457632|504175|627780|636297|636369|(506699|5067[0-6]\d|50677[0-8])|(50900\d|5090[1-9]\d|509[1-9]\d{2})|65003[1-3]|(65003[5-9]|65004\d|65005[0-1])|(65040[5-9]|6504[1-3]\d)|(65048[5-9]|65049\d|6505[0-2]\d|65053[0-8])|(65054[1-9]|6505[5-8]\d|65059[0-8])|(65070\d|65071[0-8])|65072[0-7]|(65090[1-9]|65091\d|650920)|(65165[2-9]|6516[6-7]\d)|(65500\d|65501\d)|(65502[1-9]|6550[3-4]\d|65505[0-8]))[0-9]{10,12})"; string input = @"5090402132456747 6500311231321321 6500321231321321 6500331231321321 6500341231321321 6500351231321321 6500391231321321 6500401231321321 6500451231564654 6500511231564654 6504051231321331 6504851231321321 6505411231321313 6507001321321313 6507201231321133 6509011235646432 5066998786245463 6516527887324132 6550007896242321 "; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase; 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