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
  • A character except: a, b or c
  • A character in the range: a-z
  • A character not in the range: a-z
  • A character in the range: a-z or A-Z
  • Any single character
  • Alternate - match either a or b
  • Any whitespace character
  • Any non-whitespace character
  • Any digit
  • Any non-digit
  • Any word character
  • Any non-word character
  • Match everything enclosed
  • Capture everything enclosed
  • Zero or one of a
  • Zero or more of a
  • One or more of a
  • Exactly 3 of a
  • 3 or more of a
  • Between 3 and 6 of a
  • Start of string
  • End of string
  • A word boundary
  • Non-word boundary

Regular Expression


Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @/ ^<(?i)(?:input|textarea|\\w{0,}TextBox|\\w{0,}Field).*(?:name|id)=(?:\""|\')\w+(?:\""|\').* /; string input = @"{{! my-form.hbs }} <form onsubmit={{action ""submit""}}> <label for=""name"">Name:</label> <input type=""text"" id=""name"" value={{}}> <label for=""email"">Email:</label> <input type=""email"" id=""email"" value={{}}> <label for=""message"">Message:</label> <textarea id=""message"">{{model.message}}</textarea> <button type=""submit"">Submit</button> </form> <html> <head> <title>My Form</title> </head> <body> <form> <label for=""name"">Name:</label> <input type=""text"" name=""name"" id=""name""/> <label for=""email"">Email:</label> <input type=""email"" name=""email"" id=""email""/> <label for=""message"">Message:</label> <textarea name=""message"" id=""message""></textarea> <button type=""button"" onclick=""submitForm()"">Submit</button> </form> </body> </html>"; 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: