increment variable according to numbers of clicks

I have following code:

javascript:

var counter = 0;
var totalItems = 8;
var restItems = $num-totalItems;
if (restItems==22) {
    开发者_运维技巧$('#next').click(function(e) {
        e.preventDefault(); 
        counter++;
        updatestatus();     
    });
}     

function updatestatus() {   
    totalItems = totalItems + 8 * counter;
}

HTML:

<input type = "button" id="next" value="click me">

what I want is that before I click the button, the totoalItems is equal to 8, and each time when I click it, the totoal item is added by 8, but at the moment that bit of code dosen't work and give me a very large number, any one could help me figure it out, thanks a lot.

Why are you multiplying by the counter?

totalItems = totalItems + 8;

var counter = 0;
var totalItems = 8;
var restItems = $num - totalItems;

if (restItems == 22) {
    $('#next').click(function(e) {
        e.preventDefault();
        counter++;
        updatestatus();
    });
}

function updatestatus() {
    totalItems = totalItems + 8 * counter;
}

With this code, every time you run updatestatus(), it increments totalItems by its own value and 8 * counter. You don't need to increment it:

function updatestatus() {
    totalItems = 8 + 8 * counter;
}

But ideally, I'd just simplify the code:

var counter = 0;
var totalItems = 8;
var restItems = $num - totalItems;

$('#next').click(function(e) {
    if (restItems == 22) {
        e.preventDefault();
        totalItems += 8;
    }
});