How can I implement error handling in my validators?

How can I implement error handling in my validators?

You can implement error handling by using try-catch blocks to catch exceptions and return meaningful error messages.

Can you give me an example of a validator with error handling?

Sure! Here's a simple example in JavaScript:

function validateInput(input) {
    try {
        if (!input) throw new Error('Input is required.');
        // Additional validation logic
        return 'Input is valid!';
    } catch (error) {
        return error.message;
    }
}

What if I want to validate multiple fields?

You can create a function that validates each field and collects errors. Here's an example:

function validateForm(form) {
    const errors = [];
    if (!form.username) errors.push('Username is required.');
    if (!form.email) errors.push('Email is required.');
    return errors.length ? errors : 'Form is valid!';
}

How do I handle asynchronous validation?

For asynchronous validation, you can use promises. Here's a basic example:

async function validateEmail(email) {
    try {
        const exists = await checkEmailInDatabase(email);
        if (exists) throw new Error('Email already exists.');
        return 'Email is valid!';
    } catch (error) {
        return error.message;
    }
}