username#

Built-in regex plugin for validating usernames.

Usage Scenarios#

• User Registration: Validate username input during the signup process.
• Profile Editing: Ensure the new username meets the format requirements.
• Account Verification: Verify the username when logging in or performing sensitive operations.

Examples#

import { regex } from 'funtool';

// Basic validation
const isValid = regex.checker('john_doe123').use('username').isValid();

// With error handling
const result = regex.checker('123john').use('username');
if (!result.isValid()) {
  console.log('Invalid username');
}

Pattern#

/^[a-zA-Z][a-zA-Z0-9_]{4,15}$/

Validation Rules#

• Must start with a letter (either uppercase or lowercase).
• Followed by 4 to 15 characters, which can be letters, numbers, or underscores.

Error Message#

Returns false for invalid usernames without a specific message.