鼠标滚轮的兼容写法

var addMouseWheelHandler = function(){
if (document.addEventListener) {
document.addEventListener('mousewheel', MouseWheelHandler, false); //IE9, Chrome, Safari, Oper
document.addEventListener('wheel', MouseWheelHandler, false); //Firefox
document.addEventListener('DOMMouseScroll', MouseWheelHandler, false); //Old Firefox
} else {
document.attachEvent('onmousewheel', MouseWheelHandler); //IE 6/7/8
}
},
removeMouseWheelHandler = function(){
if (document.addEventListener) {
document.removeEventListener('mousewheel', MouseWheelHandler, false); //IE9, Chrome, Safari, Oper
document.removeEventListener('wheel', MouseWheelHandler, false); //Firefox
document.removeEventListener('DOMMouseScroll', MouseWheelHandler, false); //old Firefox
} else {
document.detachEvent('onmousewheel', MouseWheelHandler); //IE 6/7/8
}
},
stopDefault = function(e) {
//W3C
if ( e && e.preventDefault )
e.preventDefault();
//IE
else
window.event.returnValue = false;
return false;
},
MouseWheelHandler = function(e) {//滚动后的处理函数
stopDefault(e);
var e = e || window.event,
value = e.wheelDelta || -e.deltaY || -e.detail,
delta = Math.max(-1, Math.min(1, value));
if (delta < 0) {//scrolling down
console.log("下滑")

}else {//scrolling up
console.log("上滑")
}
};

//调用
addMouseWheelHandler();
</script>