Question

I have a Zend_Form with a dropdown field.
When the user sets a value in the url this one should be selected as default value in this dropdown.

So what i do at the moment is this:

$parlang = $this->getRequest()->getParam('lang');
if($parlang){
    $this->view->filterForm->getElement('ddLanguage')->setValue($parlang);
}

if ($this->getRequest()->isPost()) {
        if($this->view->filterForm->isValid($_POST)){
...
...
...

No i want to check if the value of the variable is even a valid value for the dropdown? How can i check this in coorporation with the form validation. Yes i can check the variable against a array or so but this seems to be “fighting against the framework”.

So what is the Zend way to do such a thing?

Edit:
My final solution for all who are interested, is:

$parlang = $this->getRequest()->getParam('lang');
if($parlang){
    $ddLanguage = $this->view->filterForm->ddLanguage;
    if($ddLanguage->isValid($parlang)){
        $ddLanguage->setValue($parlang);
        $language = $parlang;
    }
}

Answer 1

I ran a quick test and it looks like one method you can use is Zend_Form_Element_Select::getMultiOption() to check if the language exists in the select values.

<?php

$parlang = $this->getRequest()->getParam('lang');

if ($parlang) {
    $el = $this->view->filterForm->getElement('ddLanguage');

    // attempt to get the option
    // Returns null if no such option exists, otherwise returns a
    // string with the display value for the option
    if ($el->getMultiOption($parlang) !== null) {
        $el->setValue($parlang);
    }
}