Emails Validator

Simple and efficient email address validator for Dart. Validates email syntax without using regular expressions.

Live Demo

Try the interactive web demo: Live Demo

The demo allows you to test email validation in real-time with detailed debug information.

Features

• ✅ Simple and clear validation logic
• ✅ No external dependencies
• ✅ Detailed debug information
• ✅ Support for validating lists of email addresses
• ✅ RFC standards compliance
• ✅ High performance

Installation

Add the dependency to your pubspec.yaml:

dependencies:
  emails_validator: ^1.0.2

Then run:

dart pub get

Usage

Basic Validation

import 'package:emails_validator/emails_validator.dart';

void main() {
  // Validate single email
  final isValid = EmailsValidator.validate('user@example.com');
  print(isValid); // true
  
  // Validate invalid email
  final isInvalid = EmailsValidator.validate('invalid-email');
  print(isInvalid); // false
}

Validating List of Email Addresses

final emails = [
  'user@example.com',
  'invalid-email',
  'test@domain.co.uk',
  '@example.com',
];

// Get validation results for all emails
final results = EmailsValidator.validateList(emails);
// Result: {'user@example.com': true, 'invalid-email': false, ...}

// Get only valid emails
final validEmails = EmailsValidator.getValidEmails(emails);
// Result: ['user@example.com', 'test@domain.co.uk']

// Get only invalid emails
final invalidEmails = EmailsValidator.getInvalidEmails(emails);
// Result: ['invalid-email', '@example.com']

Debug Information

The validator outputs detailed debug information to the console:

[DEBUG] EmailsValidator: Starting email validation: user@example.com
[DEBUG] EmailsValidator: Email after trim: "user@example.com"
[DEBUG] EmailsValidator: Local part: "user"
[DEBUG] EmailsValidator: Domain: "example.com"
[DEBUG] EmailsValidator: Email is valid!

Supported Formats

Valid Email Addresses

• user@example.com
• test.email@domain.co.uk
• user+tag@example.org
• user.name@example.com
• user_name@example.com
• user-name@example.com
• user123@example.com
• user@subdomain.example.com

Invalid Email Addresses

• invalid-email (no @)
• @example.com (@ at beginning)
• user@ (no domain)
• user@.com (empty domain part)
• user..name@example.com (consecutive dots)
• user@-example.com (hyphen at beginning of domain)
• user@example-.com (hyphen at end of domain)

Validation Rules

1. General Rules:

   • Email cannot be null or empty
   • Minimum length: 5 characters
   • Maximum length: 254 characters
   • Must contain exactly one @ symbol

2. Local Part (before @):

   • Cannot be empty
   • Maximum length: 64 characters
   • Allowed characters: letters, numbers, !#$%&'*+-/=?^_{|}~.`
   • Dot cannot be first or last character

3. Domain (after @):

   • Cannot be empty
   • Maximum length: 253 characters
   • Must contain at least 2 parts (e.g., example.com)
   • Each part no longer than 63 characters
   • Allowed characters: letters, numbers, hyphen
   • Hyphen cannot be first or last character of part
   • Last part (TLD) minimum 1 character (e.g. test domains like .c)

Interactive Web Demo

The project includes a Flutter Web demo application that demonstrates the email validation functionality.

Testing

Run tests:

dart test

Performance

The validator is optimized for high performance:

• No regular expressions used
• Minimal string operations
• Efficient character checking

License

MIT License