在HTML页面之间传递变量值

Question

I created this HTML calendar, when the user selects a date, JS returns a value like this:

<li class ="num" id="day6" onclick = "return checkDate(6)"> </li>

I called the value in my external JS file:

function checkDate(a) {
    a = dayNum;
    alert(dayNum);
    day = dayNum- start_day2; }

The alert works, but when I try to load this same script on another page, it alerts "undefined". I assume it's because of the reloading the value for a is not set. Is there a way around this? Sticking to Javascript only please because that's the only Language I know fairly well.

Thanks.

Answer 1

function checkDate(a) {
    var dayNum, day, start_day2;
    dayNum = a;
    start_day2 = null; //no value specified in given code
    alert(dayNum);
    day = dayNum- start_day2; 
}

Short cut to what you've shown

function checkDate(a) {
    alert(a);
}