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

/
/

Test String

Code Generator

Generated Code

$re = '/\/\*(.+?)\*\//'; $str = 'using System.Collections; using System.Collections.Generic; using UnityEngine; using UnityEngine.UI; using TMPro; using System.Text.RegularExpressions; using System; public interface IThemeable { } public class TestScript : MonoBehaviour { #region Studio Style class Program : IThemeable { static int _I = 1; delegate void DoSomething(); static DoSomething DelegateMethod = delegate { }; /* This is a multi line quote */ /*single line quote*/ /* single line quote */ /// <summary> /// The quick brown fox jumps over the lazy dog /// THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG /// </summary> static void Main(string[] args) { string normalStr = "The time now is approximately " + DateTime.Now; Uri Illegal1Uri = new Uri("http://packmyboxwith/jugs.html?q=five-dozen&t=liquor"); Regex OperatorRegex = new Regex(@"\\S#$", RegexOptions.IgnorePatternWhitespace); for (int O = 0; O < 123456789; O++) { _I += (O % 3) * ((O / 1) ^ 2) - 5; if (!OperatorRegex.IsMatch(Illegal1Uri.ToString())) { // no idea what this does!? Console.WriteLine(Illegal1Uri + normalStr); } } Program.DelegateMethod(); } static int Sum(int a, int b) { return a + b; } } #endregion }'; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php