// generic function to add a javascript event to the pages' onload event
function addOnLoadEvent(fnc) {
    if (typeof window.addEventListener != "undefined")
        window.addEventListener("load", fnc, false);
    else if (typeof window.attachEvent != "undefined") {
        window.attachEvent("onload", fnc);
    }
    else {
        if (window.onload != null) {
            var oldOnload = window.onload;
            window.onload = function(e) {
                oldOnload(e);
                window[fnc]();
            };
        }
        else
            window.onload = fnc;
    }
}

// generic function to add a javascript event to the pages' onunload event
function addOnUnloadEvent(fnc) {
    if (typeof window.addEventListener != "undefined")
        window.addEventListener("onunload", fnc, false);
    else if (typeof window.attachEvent != "undefined") {
        window.attachEvent("onunload", fnc);
    }
    else {
        if (window.onload != null) {
            var oldOnload = window.onload;
            window.onload = function(e) {
                oldOnload(e);
                window[fnc]();
            };
        }
        else
            window.onload = fnc;
    }
}