Yii how to send through ajaxButton the selected value of a combo? - ajax

Question

echo CHtml::ajaxButton (Yii::t('Listing.Listing','Associa'),
$this->createUrl('listing/addAssociation', array("id" => $model->id, "itemId"=> '5' ) ),
array('update' => '#dataToUpdate')
);
i'm using this example code (and it's working), to send an id and an itemId ('5' fixed in the example), to addAssociation.
All is working, but I've the need to pass for itemId the result of a jQuery expression. something like
"itemId" = "js: $('#myDropDown option:selected').val();"
But in this case, the js expression is not evaluated and in actionAddAssociation i see that itemId is the literal string:
"js: $('#myDropDown option:selected').val();"
how to allow an user to select a combo, and the pass the selected value to an action based on this action ?

Answer 1

You have to pass that in the ajax option's data property:
echo CHtml::ajaxButton (Yii::t('Listing.Listing','Associa'),
$this->createUrl('listing/addAssociation', array("id" => $model->id)),
array(// these are ajax options
'data' => array('itemId'=> 'js: $("#myDropDown option:selected").val()'),
// and don't use semi-colon after val(), you can also pass id here itself
'update' => '#dataToUpdate'
)
);

Answer 2

You can try to use jQuery's ajaxPrefilter to add a function that will alter your data being passed through ajax.
First, you have to register the following script on your page's initialization:
jQuery.ajaxPrefilter(function(options, originalOptions, jqXHR) {
if (originalOptions['data'] && originalOptions['data']['requestId'] === "myDropDown") {
delete originalOptions['data']['requestId'];
originalOptions['data']['itemId'] = jQuery("#myDropDown option:selected").val();
options['data'] = jQuery.param(originalOptions['data']);
}
});
Here options is a complete settings object determined for jQuery.ajax(). I pass an additional requestId parameter to identify ajax request and, to make things simplier, a view could look like this:
<?php
print CHtml::dropDownList("myDropDown", 1, array(
1 => "First",
2 => "Second",
3 => "Third"
));
print CHtml::ajaxButton(Yii::t("Listing.Listing", "Associa"), Yii::app()->createUrl("listing/addAssociation"), array(
'data' => array(
'requestId' => "myDropDown",
'id' => $model->id
),
'update' => "#dataToUpdate"
));