AJAX，JQuery，点击按钮后计算价格

Question

I want to calculate the price after a button click. I have 3 buttons which are selectable. For example : button1 = 50$, button2 = 100$, button3 = 200$ Now I want to update the price after a button click. Is there any solution to handle this? Because, If i send the Ajax request and update my html-element the price isn't added. My old price always disappear. So if the user selects button1 the price is 50$, but if the user also selects button2 my price is 100$, not $150.

Thanks :)

Answer 1

Here is the idea:

<script>
    function add(x) {
        document.getElementById('result').innerText =  +(document.getElementById('result').innerText) + x;
    }
</script>
<form>
    <input type="button" onclick="add(50)" value="50">
    <input type="button" onclick="add(100)" value="100">
    <input type="button" onclick="add(200)" value="200">
</form>
<div id='result'></div>

Note: +(x) forces conversion of x to number