I'm trying to create my custom field for admin interface and ensure it validates with JS.

I have my own custom field:

<?php

/**
 * Textarea that only allows emails separated by commas.
 *
 * @author Artūras 'arturaz' Šlajus <x11@arturaz.net>
 */
class EmailAreaField extends EmailField {
  const ERROR_MESSAGE = "One of the emails in the field is invalid.";
  const EMAIL_REGEXP = '/^.+@.+\.[a-z]+$/i';

  public function validate() {
    foreach (split(",", $this->value) as $email) {
      $email = trim($email);

      if (! preg_match(self::EMAIL_REGEXP, $email)) {
        $validator->validationError(
          $this->name,
          self::ERROR_MESSAGE,
          "validation"
        );

        return false;
      }
    }

    return true;
  }

  public function jsValidation() {
    $formID = $this->form->FormName();
		$error = self::ERROR_MESSAGE;
    $regexp = self::EMAIL_REGEXP;
		$jsFunc =<<<JS
Behaviour.register({
	"#$formID": {
		validateEmailAreaField: function(fieldName) {
			var el = _CURRENT_FORM.elements[fieldName];
			if(!el || !el.value) return true;

      var parts = el.value.split(',');
      for (var index = 0; index < parts.length; index++) {
        var part = parts[index].strip();
        if (! el.value.match($regexp)) {
          validationError(el, "$error", "validation");
          return false;
        }
      }

      return true;
		}
	}
});
JS;
		//fix for the problem with more than one form on a page.
		Requirements::customScript($jsFunc, 'func_validateEmailAreaField' . '_' . $formID);

		return <<<JS
if(typeof fromAnOnBlur != 'undefined'){
	if(fromAnOnBlur.name == '$this->name')
		$('$formID').validateEmailAreaField('$this->name');
}else{
	$('$formID').validateEmailAreaField('$this->name');
}
JS;
  }
}
?>

Server validation works fine. However it seems that nobody cares about my jsValidation() method. If I just use EmailField in my form instead of this class - it works. But as soon as I switch to my class, it suddently stops working even if I do this!

<?php

/**
 * Textarea that only allows emails separated by commas.
 *
 * @author Artūras 'arturaz' Šlajus <x11@arturaz.net>
 */
class EmailAreaField extends EmailField {
  public function jsValidation() {
    return parent::jsValidation();
  }
}
?>

Any ideas what's happening? :/

Also it seems that:

<?php

/**
 * Textarea that only allows emails separated by commas.
 *
 * @author Artūras 'arturaz' Šlajus <x11@arturaz.net>
 */
class EmailAreaField extends EmailField {
  const ERROR_MESSAGE = "One of the emails in the field is invalid.";
  const EMAIL_REGEXP = '/^.+@.+\.[a-z]+$/i';

  public function validate() {
    foreach (split(",", $this->value) as $email) {
      $email = trim($email);

      if (! preg_match(self::EMAIL_REGEXP, $email)) {
        $validator->validationError(
          $this->name,
          self::ERROR_MESSAGE,
          "validation"
        );

        return false;
      }
    }

    return true;
  }

  public function jsValidation() {
    return parent::jsValidation();
  }
}
?>

fails, but

<?php

/**
 * Textarea that only allows emails separated by commas.
 *
 * @author Artūras 'arturaz' Šlajus <x11@arturaz.net>
 */
class EmailAreaField extends EmailField {
  const ERROR_MESSAGE = "One of the emails in the field is invalid.";
  const EMAIL_REGEXP = '/^.+@.+\.[a-z]+$/i';

  public function jsValidation() {
    return parent::jsValidation();
  }
}
?>

Uses EmailField JS validation logic. So removing server-side validator somehow affects my client-side validator?