一件容易的事。

var scrollIt = function(time) {
    // time = scroll time in ms
    var start = new Date().getTime(),
        scroll = document.documentElement.scrollTop + document.body.scrollTop,
        timer = setInterval(function() {
            var now = Math.min(time,(new Date().getTime())-start)/time;
            document.documentElement.scrollTop
                = document.body.scrollTop = (1-time)/start*scroll;
            if( now == 1) clearTimeout(timer);
        },25);
}

另一种基于上述解决方案的跨浏览器方法

function doScrollTo(to, duration) {
    var element = document.documentElement;

        var start = element.scrollTop,
        change = to - start,
        increment = 20,
        i = 0;

    var animateScroll = function(elapsedTime) {
        elapsedTime += increment;
        var position = easeInOut(elapsedTime, start, change, duration);
        if (i === 1 && window.scrollY === start) {
            element = document.body;
            start = element.scrollTop;
        }
        element.scrollTop = position;
        if (!i) i++;
        if (elapsedTime < duration) {
            setTimeout(function() {
                animateScroll(elapsedTime);
            }, increment);
        }
    };

    animateScroll(0);
}

诀窍在于控制实际的滚动变化，如果它为零，则更改滚动元素。

我看到上面大多数/所有的帖子都是用javascript搜索按钮的。这是有效的，只要你只有一个按钮。我建议在按钮内定义一个“onclick”元素。然后，“onclick”将调用该函数，使其滚动。

如果你这样做，你可以使用多个按钮，只要按钮看起来像这样:

<button onclick="scrollTo(document.body, 0, 1250)">To the top</button>

我已经选择了@timwolla answer的@akai版本，并添加了stopAnimation函数作为返回，所以在开始新的动画之前，旧的动画可以停止。

if ( this.stopAnimation )
    this.stopAnimation()

    this.stopAnimation = scrollTo( el, scrollDestination, 300 )


// definitions

function scrollTo(element, to, duration) {
    var start = element.scrollTop,
        change = to - start,
        increment = 20,
        timeOut;

    var animateScroll = function(elapsedTime) {        
        elapsedTime += increment;
        var position = easeInOut(elapsedTime, start, change, duration);                        
        element.scrollTop = position; 
        if (elapsedTime < duration) {
            timeOut = setTimeout(function() {
                animateScroll(elapsedTime);
            }, increment);
        }
    };

    animateScroll(0);

    return stopAnimation

    function stopAnimation() {
        clearTimeout( timeOut )
    }
}

function easeInOut(currentTime, start, change, duration) {
    currentTime /= duration / 2;
    if (currentTime < 1) {
        return change / 2 * currentTime * currentTime + start;
    }
    currentTime -= 1;
    return -change / 2 * (currentTime * (currentTime - 2) - 1) + start;
}

线性滚动动画到底部。纯JS，没有JQuery。也许我的解决方案会对某人有所帮助。

let action_count = 8;
let speed_ms = 15;
let objDiv = document.getElementsByClassName('js_y5_area3').item(0);

let scroll_height = objDiv.scrollHeight;
let window_height = objDiv.offsetHeight;

let scroll_top = objDiv.scrollTop;
let need_scroll_top = scroll_height - window_height;

if (scroll_top < need_scroll_top)
{
    let step = Math.ceil((need_scroll_top - scroll_top) / action_count);

    let scrollInterval = setInterval(function()
    {
        scroll_top += step;
        objDiv.scrollTop = scroll_top;

        if (scroll_top >= need_scroll_top)
        {
            clearInterval(scrollInterval);
        }

    }, speed_ms);
}

你可以改变变量action_count, speed_ms来配置滚动动画。

看来已经有很多解决方案了。不管怎样，这是另一个，使用简化方程。

// first add raf shim
// http://www.paulirish.com/2011/requestanimationframe-for-smart-animating/
window.requestAnimFrame = (function(){
  return  window.requestAnimationFrame       ||
          window.webkitRequestAnimationFrame ||
          window.mozRequestAnimationFrame    ||
          function( callback ){
            window.setTimeout(callback, 1000 / 60);
          };
})();

// main function
function scrollToY(scrollTargetY, speed, easing) {
    // scrollTargetY: the target scrollY property of the window
    // speed: time in pixels per second
    // easing: easing equation to use

    var scrollY = window.scrollY || document.documentElement.scrollTop,
        scrollTargetY = scrollTargetY || 0,
        speed = speed || 2000,
        easing = easing || 'easeOutSine',
        currentTime = 0;

    // min time .1, max time .8 seconds
    var time = Math.max(.1, Math.min(Math.abs(scrollY - scrollTargetY) / speed, .8));

    // easing equations from https://github.com/danro/easing-js/blob/master/easing.js
    var easingEquations = {
            easeOutSine: function (pos) {
                return Math.sin(pos * (Math.PI / 2));
            },
            easeInOutSine: function (pos) {
                return (-0.5 * (Math.cos(Math.PI * pos) - 1));
            },
            easeInOutQuint: function (pos) {
                if ((pos /= 0.5) < 1) {
                    return 0.5 * Math.pow(pos, 5);
                }
                return 0.5 * (Math.pow((pos - 2), 5) + 2);
            }
        };

    // add animation loop
    function tick() {
        currentTime += 1 / 60;

        var p = currentTime / time;
        var t = easingEquations[easing](p);

        if (p < 1) {
            requestAnimFrame(tick);

            window.scrollTo(0, scrollY + ((scrollTargetY - scrollY) * t));
        } else {
            console.log('scroll done');
            window.scrollTo(0, scrollTargetY);
        }
    }

    // call it once to get started
    tick();
}

// scroll it!
scrollToY(0, 1500, 'easeInOutQuint');