Call class in AJAX responce text

I have div in which I am getting ajax response

<div id="demo"></div>

And in response I am getting three buttons with id and values

<button type="button" class="Model" onclick="ModelAppAll(<?php echo $i; ?>)">Approve All</button>
<button type="button" class="Model" onclick="ModelRejAll(<?php echo $i; ?>)">Reject All</button>

Now I want to call a function and get the $i values in alert box like

function ModelAppReqId1(){
    alert(this.id);
}

Or like this with jquery

$(".model").click(function{
    alert(this.value);
});

In short I want work with AJAX response like actual DOM element. I am not able to find any class [model] in responce text. Give some Ideas Please