你可以确定鼠标的方向。

$(window).on('mousewheel DOMMouseScroll', function (e) {
    var delta = e.originalEvent.wheelDelta ? 
                   e.originalEvent.wheelDelta : -e.originalEvent.detail;

    if (delta >= 0) {
        console.log('scroll up');
    } else {
        console.log('scroll down');
    }
});

检查当前的scrollTop和之前的scrollTop

var lastScrollTop = 0;
$(window).scroll(function(event){
   var st = $(this).scrollTop();
   if (st > lastScrollTop){
       // downscroll code
   } else {
      // upscroll code
   }
   lastScrollTop = st;
});

在滚动的元素的.data()中存储一个增量，然后就可以测试滚动到达顶部的次数。

在元素的.data()中，您可以存储JSON和测试值来启动事件

{ top : 1,
   first_top_event: function(){ ...},
   second_top_event: function(){ ...},
   third_top_event: function(){ ...},
   scroll_down_event1: function(){ ...},
   scroll_down_event2: function(){ ...}
}

存储之前的滚动位置，然后查看新的滚动位置是否大于或小于该位置。

这里有一个避免任何全局变量的方法(在这里可以找到):

(function () {
    var previousScroll = 0;

    $(window).scroll(function(){
       var currentScroll = $(this).scrollTop();
       if (currentScroll > previousScroll){
           alert('down');
       } else {
          alert('up');
       }
       previousScroll = currentScroll;
    });
}()); //run this anonymous function immediately

保持超级简单:

jQuery事件监听器

$(window).on('wheel', function(){
  whichDirection(event);
});

香草JavaScript事件监听器

if(window.addEventListener){
  addEventListener('wheel', whichDirection, false);
} else if (window.attachEvent) {
  attachEvent('wheel', whichDirection, false);
}

功能不变:

function whichDirection(event){
  console.log(event + ' WheelEvent has all kinds of good stuff to work with');
  var scrollDirection = event.deltaY;
  if(scrollDirection === 1){
    console.log('meet me at the club, going down', scrollDirection);
  } else if(scrollDirection === -1) {
    console.log('Going up, on a tuesday', scrollDirection);
  }
}

我在这里写了一篇更深入的文章 ​​​​​​​