How to validate a checkbox in ZF2

Question

I've read numerous workarounds for Zend Framework's lack of default checkbox validation.

I have recently started using ZF2 and the documentation is a bit lacking out there.

Can someone please demonstrate how I can validate a checkbox to ensure it was ticked, using the Zend Form and Validation mechanism? I'm using the array configuration for my Forms (using the default set-up found in the example app on the ZF website).

Answer 1

Try this

Form element :

$this->add(array(
            'type' => 'Zend\Form\Element\Checkbox',
            'name' => 'agreeterms',
            'options' => array(
                'label' => 'I agree to all terms and conditions',
                'use_hidden_element' => true,
                'checked_value' => 1,
                'unchecked_value' => 'no'
            ),
        ));

In filters, add digit validation

use Zend\Validator\Digits; // at top

$inputFilter->add($factory->createInput(array(
                        'name' => 'agreeterms',
                        'validators' => array(
                            array(
                                'name' => 'Digits',
                                'break_chain_on_failure' => true,
                                'options' => array(
                                    'messages' => array(
                                        Digits::NOT_DIGITS => 'You must agree to the terms of use.',
                                    ),
                                ),
                            ),
                        ),
                    )));

Answer 2

You could also just drop the hidden form field (which I find a bit weird from a purist HTML point of view) from the options instead of setting its value to 'no' like this:

$this->add(array(
        'type' => 'Zend\Form\Element\Checkbox',
        'name' => 'agreeterms',
        'options' => array(
            'label' => 'I agree to all terms and conditions',
            'use_hidden_element' => false
        ),
    ));

Answer 3

I had the same problem and did something similar to Optimus Crew's suggestion but used the Identical Validator.

If you don't set the checked_value option of the checkbox and leave it as the default it should pass in a '1' when the data is POSTed. You can set it if you require, but make sure you're checking for the same value in the token option of the validator.

$this->filter->add(array(
        'name' => 'agreeterms',
        'validators' => array(
            array(
                'name' => 'Identical',
                'options' => array(
                    'token' => '1',
                    'messages' => array(
                        Identical::NOT_SAME => 'You must agree to the terms of use.',
                    ),
                ),
            ),
        ),
    ));

This won't work if you use the option 'use_hidden_element' => false for the checkbox for the form. If you do this, you'll end up displaying the default NotEmpty message Value is required and can't be empty