How do I write a custom validator for a zend form element with customized error messages?

Question

I have a question field with a list of allowed characters : A-Z,0-9,colon (:), question mark (?), comma(,), hyphen(-), apostrophe ('). I have the regex which works fine, in the fashion :

 $question->addValidator('regex', true, array(<regular expresstion>))

The default error message is something like ''' does not match against pattern ''

I want to write a custom error message that says ' is not allowed in this field'

Is there a simple way to do it using the existing zend components that I'm missing?

Is writing a custom validator the only way to achieve what I'm trying to achieve? If yes, how do I write a custom validator (I looked at the documentation and didn't quite understand how I can customize the error messages) If there is any other way, I'd most appreciate that input too.

Thanks for taking the time to answer this!

Answer 1

Yes, the custom validator fits your needs. On how to write it, please refer to this manual.

With regards to a code snippet, here's a simple validator(partial) for validating employer ID

protected $_messageTemplates = array(
    self::UNIQUE => 'The id provided is already in use',
    );

public function isValid($value, $context = null)
{
    $this->_setValue($value);

    $personnel = new Personnel();
    $isValid = true;

    if( $personnel->isExistingIdEmployee($value) && ($value != $this->_id) ) {
        $this->_error(self::UNIQUE);
        $isValid = false;
    }

    return $isValid;
}