Simple Form Validation Library

This is a simple form validation library for JavaScript/TypeScript to validate form fields. It provides common validators (required, minLength, maxLength, email, numeric, phone number, etc.) and allows easy integration into your forms.

Features

• Easy-to-use API for adding validation rules
• Built-in common validation rules such as required, minLength, email, etc.
• Ability to add custom validation rules
• Provides error messages when validation fails

Installation

To install the library, run the following command in your project directory:

bash npm install tmt-form-validator

Usage Example:

Here's the code written using markdown formatting:

First, we import the necessary components:

import { FormValidator, Validators } from 'simple-form-validation-lib';

Then, we create a new form validator:

const formValidator = new FormValidator();

Add validation rules for the username field

formValidator.addFieldRules('username', [ Validators.required('Username is required'), Validators.minLength(3, 'Username must be at least 3 characters'), ]);

Add validation rules for the email field

formValidator.addFieldRules('email', [ Validators.required('Email is required'), Validators.email('Invalid email address'), ]);

Validate a form

const formValues = { username: 'John', email: '[email protected]', };

Validate the form values

const errors = formValidator.validateAll(formValues);

if (formValidator.isValid(errors)) { console.log('Form is valid!'); } else { console.log('Validation Errors:', errors); }

Available Validators

| Validator | Description |-----|----- | required(message) | Ensures the field is not empty | minLength(length, message) | Ensures the field has at least the specified length | maxLength(length, message) | Ensures the field does not exceed the specified length | email(message) | Ensures the field contains a valid email address | numeric(message) | Ensures the field is a valid number | phoneNumber(message) | Ensures the field contains a valid phone number (in E.164 format) | pattern(regex, message) | Ensures the field matches the specified regular expression pattern | equalTo(value, message) | Ensures the field value is equal to another value

Methods

| Method | Description |-----|----- | addFieldRules(field: string, rules: ValidationRule[]): void | Adds validation rules for a specific field | validateField(field: string, value: any): string[] | Validates a single field and returns an array of error messages | validateAll(values: Record<string, any>): Record<string, string[]> | Validates all fields in the form and returns a record of errors | isValid(errors: Record<string, string[]>): boolean | Checks if the form is valid (no errors)

License

This package is licensed under the MIT License.

Feel free to contribute to this project by submitting issues or pull requests on our GitHub repository.