清除子元素继承父元素鼠标移入移出事件

function contains(parentNode, childNode) {
        if (parentNode.contains) {
            return parentNode != childNode && parentNode.contains(childNode);
        } else {
            return !!(parentNode.compareDocumentPosition(childNode) & 16);
        }
    }
    
    function checkHover(e,target){
        if (getEvent(e).type=="mouseover")  {
            return !contains(target,getEvent(e).relatedTarget||getEvent(e).fromElement) && !((getEvent(e).relatedTarget||getEvent(e).fromElement)===target);
        } else {
            return !contains(target,getEvent(e).relatedTarget||getEvent(e).toElement) && !((getEvent(e).relatedTarget||getEvent(e).toElement)===target);
        }
    }function getEvent(e){
        return e||window.event;
    }