Question

Today, I have come across a bug in my Zend Framework application. This is the case:

I have a form with an element that has a regex validator on it. When testing the form, I found out that I can not provide the value 0 for the element. Zend gives me an error, telling me that I have not filled in the element.

The element:

$element = $this->createElement( "text", "amount", array( "label" => "Amount", "required" => true ) );
$element->addValidator( 'regex', false, array( '/^[-]?([0-9]+)(([,.][0-9]+)+)?$/' ) );

Can anyone tell me what the reason might be that Zend tells me I have not filled in the element when the submitted value is 0?

Thx

Answer 1

It’s very simple, when you set “required” as true, Zend_Form_Element automatically adds a notEmpty() validator at the top of the validators stack.

Therefore, any null, 0, “”, etc. values are considered false, and this validator set an error to your form.

See the manual for more information:

Default behaviour for Zend_Validate_NotEmpty

By default, this validator works differently than you would expect when you’ve worked
with PHP’s empty() function. In particular, this validator will
evaluate both the integer 0 and string ‘0’ as empty.

$valid = new Zend_Validate_NotEmpty();
$value  = '';
$result = $valid->isValid($value);
// returns false