Question

How to make the function only runs once per button?
if clicks in “click me” only works once, and the same for the other buttons.
Order not to put much code, I put an example..:
http://jsbin.com/apexod/2/edit

<input type="button" value="click me" onclick="hello('Jhon')"><br>
<input type="button" value="click me1" onclick="hello('Gerard')"><br>
<input type="button" value="click me2" onclick="hello('Kaoru')">
<script>
function hello(id){
    alert("hello "+id);
}
</script>

Answer 1

You can send the button element reference along to the function, and remove the event from the button:

<input type="button" value="click me" onclick="hello(this,'Jhon')"><br>
<input type="button" value="click me1" onclick="hello(this,'Gerard')"><br>
<input type="button" value="click me2" onclick="hello(this,'Kaoru')">
<script>
function hello(el, id){
    alert("hello " + id);
    el.onclick = null;
}
</script>

Demo: http://jsfiddle.net/Guffa/CDjGY/