ie9 已经支持 stopPropagation 遏止冒泡

ie9 已经支持 stopPropagation 阻止冒泡
    $(function () {
        $(window).mousedown(function(e){
            alert(typeof e.stopPropagation); //显示的是function
        });
    });

ie9 已经支持 stopPropagation 阻止冒泡