String Validify #

A lightweight, zero-dependency Dart package for string validation, formatting, and common input checks. Perfect for form validation in Flutter apps or any Dart project.

Features #

• Email Validation - Validate, extract domain/username, mask for privacy
• Phone Validation - Validate international numbers, sanitize, mask
• URL Validation - Validate with/without scheme, extract domain, auto-add scheme
• Credit Card Validation - Luhn algorithm check, card type detection, masking, formatting
• Password Validation - Configurable rules, strength scoring
• String Utilities - Capitalize, titleCase, camelCase, snakeCase, truncate, mask, initials, and more
• Common Validators - Required, minLength, maxLength, pattern matching, range checks

Installation #

Add string_validify to your pubspec.yaml:

dependencies:
  string_validify: ^1.0.0

Then run:

dart pub get

Usage #

Email Validation #

import 'package:string_validify/string_validify.dart';

EmailValidator.isValid('user@example.com');       // true
EmailValidator.validate('bad-email');              // 'Invalid email address'
EmailValidator.getDomain('user@gmail.com');        // 'gmail.com'
EmailValidator.mask('john.doe@gmail.com');         // 'j******e@gmail.com'

Phone Validation #

PhoneValidator.isValid('+1234567890');             // true
PhoneValidator.sanitize('+1 (234) 567-890');       // '+1234567890'
PhoneValidator.mask('+1234567890');                // '+12****7890'

URL Validation #

UrlValidator.isValid('https://example.com');       // true
UrlValidator.isValidLoose('example.com');           // true (no scheme required)
UrlValidator.ensureScheme('example.com');           // 'https://example.com'
UrlValidator.getDomain('https://example.com/path');// 'example.com'

Credit Card Validation #

CreditCardValidator.isValid('4111111111111111');    // true (Luhn check)
CreditCardValidator.getCardType('4111...');         // CardType.visa
CreditCardValidator.mask('4111111111111111');        // '**** **** **** 1111'
CreditCardValidator.format('4111111111111111');      // '4111 1111 1111 1111'

Password Validation #

PasswordValidator.isValid('Abcdefg1');                      // true
PasswordValidator.getStrength('Abcdefghij12345!').label;    // 'Very Strong'
PasswordValidator.validate('weak');                          // 'Password must be at least 8 characters'

// Custom rules
PasswordValidator.validate('MyPass1',
  minLength: 10,
  requireSpecialChar: true,
);

String Utilities #

StringUtils.capitalize('hello world');     // 'Hello world'
StringUtils.titleCase('hello world');      // 'Hello World'
StringUtils.camelCase('hello world');      // 'helloWorld'
StringUtils.snakeCase('helloWorld');        // 'hello_world'
StringUtils.truncate('Hello world', 5);    // 'Hello...'
StringUtils.mask('SensitiveData');         // 'Se*********ta'
StringUtils.initials('John Doe');          // 'JD'
StringUtils.wordCount('Hello world');      // 2
StringUtils.isNumeric('12345');            // true
StringUtils.isAlpha('hello');              // true

Common Validators #

CommonValidator.required('');                          // 'This field is required'
CommonValidator.minLength('hi', 5);                    // 'Must be at least 5 characters'
CommonValidator.maxLength('hello world', 5);           // 'Must be at most 5 characters'
CommonValidator.matches('abc', 'xyz');                  // 'Values do not match'
CommonValidator.numberInRange('5', min: 1, max: 10);   // null (valid)

Flutter Form Integration #

All validate() methods return String?, making them perfect for Flutter's TextFormField:

TextFormField(
  validator: (value) => EmailValidator.validate(value),
);

TextFormField(
  validator: (value) => PasswordValidator.validate(value,
    minLength: 10,
    requireSpecialChar: true,
  ),
);

TextFormField(
  validator: (value) => CommonValidator.required(value, fieldName: 'Name'),
);

License #

MIT License - see LICENSE for details.