Yii ajax forms

My task is simple, I want to create a simple view for simple library : you dropdown a list of books then submit to borrow that book to the user. the call must be in AJAX, A function of adding a new user exist already but I want to switch to AJAX. This task shouldnt take more than half day if you use Yii The tables are ready and the main structure also, you just need to create the View "borrow"