function addEvent(elem, evtType, func, capture) {
    capture = (capture) ? capture : false;
    if (elem.addEventListener) {
        elem.addEventListener(evtType, func, capture);
    } else if (elem.attachEvent) {
        elem.attachEvent("on" + evtType, func);
    } else {
        elem["on" + evtType] = func;
    }
}
function removeEvent(elem, evtType, func, capture) {
    capture = (capture) ? capture : false;
    if (elem.removeEventListener) {
        elem.removeEventListener(evtType, func, capture);
    } else if (elem.attachEvent) {
        elem.detatchEvent("on" + evtType, func);
    } else {
        elem["on" + evtType] = null;
    }
}

function addOnLoadEvent(func) {
    if (window.addEventListener || window.attachEvent) {
        addEvent(window, "load", func, false);
    } else {
        var oldQueue = (window.onload) ? window.onload : function() { };
        window.onload = function() {
            oldQueue();
            func();
        }
    }
}