滚动事件

滚动事件在FF中表现得很奇怪(它会因为平滑滚动而被触发很多次)，但它是有效的。

注意:滚动事件实际上是在使用光标键或鼠标滚轮拖动滚动条时触发的。

//creates an element to print the scroll position
$("<p id='test'>").appendTo("body").css({
    padding: "5px 7px",
    background: "#e9e9e9",
    position: "fixed",
    bottom: "15px",
    left: "35px"
});

//binds the "scroll" event
$(window).scroll(function (e) {
    var target = e.currentTarget,
        self = $(target),
        scrollTop = window.pageYOffset || target.scrollTop,
        lastScrollTop = self.data("lastScrollTop") || 0,
        scrollHeight = target.scrollHeight || document.body.scrollHeight,
        scrollText = "";

    if (scrollTop > lastScrollTop) {
        scrollText = "<b>scroll down</b>";
    } else {
        scrollText = "<b>scroll up</b>";
    }

    $("#test").html(scrollText +
      "<br>innerHeight: " + self.innerHeight() +
      "<br>scrollHeight: " + scrollHeight +
      "<br>scrollTop: " + scrollTop +
      "<br>lastScrollTop: " + lastScrollTop);

    if (scrollHeight - scrollTop === self.innerHeight()) {
      console.log("► End of scroll");
    }

    //saves the current scrollTop
    self.data("lastScrollTop", scrollTop);
});

轮事件

你也可以看看MDN，它揭露了关于车轮事件的大量信息。

注意:wheel事件仅在使用鼠标滚轮时触发;光标键和拖动滚动条不会触发事件。

我阅读了文档和示例:跨浏览器监听此事件 在FF, IE, chrome, safari进行了一些测试后，我得到了这个片段:

//creates an element to print the scroll position
$("<p id='test'>").appendTo("body").css({
    padding: "5px 7px",
    background: "#e9e9e9",
    position: "fixed",
    bottom: "15px",
    left: "15px"
});

//attach the "wheel" event if it is supported, otherwise "mousewheel" event is used
$("html").on(("onwheel" in document.createElement("div") ? "wheel" : "mousewheel"), function (e) {
    var evt = e.originalEvent || e;

    //this is what really matters
    var deltaY = evt.deltaY || (-1 / 40 * evt.wheelDelta), //wheel || mousewheel
        scrollTop = $(this).scrollTop() || $("body").scrollTop(), //fix safari
        scrollText = "";

    if (deltaY > 0) {
        scrollText = "<b>scroll down</b>";
    } else {
        scrollText = "<b>scroll up</b>";
    }

    //console.log("Event: ", evt);
    $("#test").html(scrollText +
      "<br>clientHeight: " + this.clientHeight +
      "<br>scrollHeight: " + this.scrollHeight +
      "<br>scrollTop: " + scrollTop +
      "<br>deltaY: " + deltaY);
});

使用这个来找到滚动方向。这只是为了找到垂直滚动的方向。支持所有跨浏览器。

    var scrollableElement = document.getElementById('scrollableElement');

    scrollableElement.addEventListener('wheel', findScrollDirectionOtherBrowsers);

    function findScrollDirectionOtherBrowsers(event){
        var delta;

        if (event.wheelDelta){
            delta = event.wheelDelta;
        }else{
            delta = -1 * event.deltaY;
        }

        if (delta < 0){
            console.log("DOWN");
        }else if (delta > 0){
            console.log("UP");
        }

    }

例子

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

我有弹性滚动的问题(滚动弹跳，橡皮筋)。 如果接近页面顶部，忽略下滚动事件对我来说是有效的。

var position = $(window).scrollTop();
$(window).scroll(function () {
    var scroll = $(window).scrollTop();
    var downScroll = scroll > position;
    var closeToTop = -120 < scroll && scroll < 120;
    if (downScroll && !closeToTop) {
        // scrolled down and not to close to top (to avoid Ipad elastic scroll-problems)
        $('.top-container').slideUp('fast');
        $('.main-header').addClass('padding-top');
    } else {
        // scrolled up
        $('.top-container').slideDown('fast');
        $('.main-header').removeClass('padding-top');
    }
    position = scroll;
});

为什么没有人使用滚动的jQuery返回的事件对象?

$window.on('scroll', function (event) {
    console.group('Scroll');
    console.info('Scroll event:', event);
    console.info('Position:', this.pageYOffset);
    console.info('Direction:', event.originalEvent.dir); // Here is the direction
    console.groupEnd();
});

我使用铬，我没有检查其他浏览器，如果他们有dir属性。

你应该试试这个

var scrl
$(window).scroll(function(){
        if($(window).scrollTop() < scrl){
            //some code while previous scroll
        }else{
            if($(window).scrollTop() > 200){
                //scroll while downward
            }else{//scroll while downward after some specific height
            }
        }
        scrl = $(window).scrollTop();
    });