Javascript page reload while maintaining current window position

Question

How do I refresh the page using Javascript without the page returning to the top.

My page refreshes using a timer but the problem is it goes back to the top every time it reloads. It should be able to retain the current position of the page as it reloads.

P.S. Additional mouse events are welcome if necessary to be a part of your suggestion. I'm actually thinking of #idname to target on refresh but my HTML elements don't have IDs, only classes.

Answer 1

If you use JavaScript, this code will do the trick.

var cookieName = "page_scroll";
var expdays = 365;

// An adaptation of Dorcht's cookie functions.

function setCookie(name, value, expires, path, domain, secure) {
    if (!expires) expires = new Date();
    document.cookie = name + "=" + escape(value) + 
        ((expires == null) ? "" : "; expires=" + expires.toGMTString()) +
        ((path    == null) ? "" : "; path=" + path) +
        ((domain  == null) ? "" : "; domain=" + domain) +
        ((secure  == null) ? "" : "; secure");
}

function getCookie(name) {
    var arg = name + "=";
    var alen = arg.length;
    var clen = document.cookie.length;
    var i = 0;
    while (i < clen) {
        var j = i + alen;
        if (document.cookie.substring(i, j) == arg) {
            return getCookieVal(j);
        }
        i = document.cookie.indexOf(" ", i) + 1;
        if (i == 0) break;
    }
    return null;
}

function getCookieVal(offset) {
    var endstr = document.cookie.indexOf(";", offset);
    if (endstr == -1) endstr = document.cookie.length;
    return unescape(document.cookie.substring(offset, endstr));
}

function deleteCookie(name, path, domain) {
    document.cookie = name + "=" +
        ((path   == null) ? "" : "; path=" + path) +
        ((domain == null) ? "" : "; domain=" + domain) +
        "; expires=Thu, 01-Jan-00 00:00:01 GMT";
}

function saveScroll() {
    var expdate = new Date();
    expdate.setTime(expdate.getTime() + (expdays*24*60*60*1000)); // expiry date

    var x = document.pageXOffset || document.body.scrollLeft;
    var y = document.pageYOffset || document.body.scrollTop;
    var data = x + "_" + y;
    setCookie(cookieName, data, expdate);
}

function loadScroll() {
    var inf = getCookie(cookieName);
    if (!inf) { return; }
    var ar = inf.split("_");
    if (ar.length == 2) {
        window.scrollTo(parseInt(ar[0]), parseInt(ar[1]));
    }
}

This works by using a cookie to remember the scroll position.

Now just add

onload="loadScroll()" onunload="saveScroll()"

to your body tag and all will be well.

Source(s): http://www.huntingground.freeserve.co.uk/main/mainfram.htm?../scripts/cookies/scrollpos.htm