form-validator

A simple forms validation library meant to be used with browserify.

To install:

npm install form-validator

To create a form (in coffee-script):

validator = require 'formvalidator'

check = validator.check

FormValidator = validator.FormValidator

registrationForm = new FormValidator()
registrationForm.add 'email', (form) ->
    if form.email == ''
        'An email is required.'

registrationForm.add 'email', (form) ->
    if form.email != '' and not check.isEmail form.email
        'Invalid email.'

registrationForm.add 'password', (form) ->
    if form.password == ''
        'A password is required.'

registrationForm.add 'confirmPassword', (form) ->
    if form.password != form.confirmPassword
        'Passwords must match.'

exports.registrationForm = registrationForm

The key points from above are the instantiation of the FormValidator() type. This type has 3 methods on it the first is the add method, this takes two arguments, the first is the name="" field of the input element you are validating. This only tells the library which field you want your validation error associated with. The second is a validation method, this method has a single argument that is the pre-parsed form (req.body); it also either returns a string (signifying an error) or nothing/null signifying no error.

Here is an example of checking a form server side:

registrationForm = require('registrationForm').registrationForm

app.post '/registration', (req, res) ->
    //errors is an array of { name: 'name', message: 'error message' }
    errors = registrationForm.validate req.body

    if errors.length > 0
        res.render 'registration', req.body
    else
        res.render 'success'

Here is an example of checking a form client side:

<script type="text/javascript">
    var $ = require('jquery')
    var registrationForm = require('./registrationForm').registrationForm

    //attaches to the form by the form id
    $(document).ready(function() { registrationForm.clientSetup('registrationForm') })
</script>

<form id="registrationForm" action="/registration" method="post">
    
</form>

Once your form is setup you can add error placeholders to it. For field errors you can place an element with error="fieldName" on it to automatically display the error text when an error occurs. e.g.

<span error="email"></span>

To display all errors you just need to add a

container. This will list all validation errors inside of it.

For some pre-made validators you can use: check = require('form-validator').check

This has a number of methods that will help make it easier to validate forms (contributions are appreciated).

That's it, if you have any questions please feel free to ask.