我正在寻找一个简单的,跨浏览器“滚动到顶部”的动画,我可以应用到一个链接。我不想需要一个JS库,如jQuery/Moo等。
// jQuery Equivilant to convert to pure JS...
$('html, body').animate({scrollTop:0}, 400);
对于那些在跳进图书馆之前应该100%学习JS的人来说,我是一个完美的例子。:(
我正在寻找一个简单的,跨浏览器“滚动到顶部”的动画,我可以应用到一个链接。我不想需要一个JS库,如jQuery/Moo等。
// jQuery Equivilant to convert to pure JS...
$('html, body').animate({scrollTop:0}, 400);
对于那些在跳进图书馆之前应该100%学习JS的人来说,我是一个完美的例子。:(
当前回答
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');
其他回答
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;
}
还有一种方法是使用window.scrollBy
JSFiddle
function scroll(pxPerFrame, duration) { if (!pxPerFrame || !duration) return; const end = new Date().getTime() + duration; step(); function step() { window.scrollBy(0, pxPerFrame); if (new Date().getTime() < end) { window.setTimeout(step, 1000 / 60); } else { console.log('done scrolling'); } } } body { width: 200px; } <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p> <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p> <p> <button onclick="scroll(-5, 3000)"> scroll(-5, 3000) </button> </p>
基于这里的一些答案,但使用了一些简单的数学,使用正弦曲线进行平稳过渡:
scrollTo(element, from, to, duration, currentTime) {
if (from <= 0) { from = 0;}
if (to <= 0) { to = 0;}
if (currentTime>=duration) return;
let delta = to-from;
let progress = currentTime / duration * Math.PI / 2;
let position = delta * (Math.sin(progress));
setTimeout(() => {
element.scrollTop = from + position;
this.scrollTo(element, from, to, duration, currentTime + 10);
}, 10);
}
用法:
// Smoothly scroll from current position to new position in 1/2 second.
scrollTo(element, element.scrollTop, element.scrollTop + 400, 500, 0);
注:注意ES6风格
这是一种基于上述答案的跨浏览器方法
function scrollTo(to, duration) {
if (duration < 0) return;
var scrollTop = document.body.scrollTop + document.documentElement.scrollTop;
var difference = to - scrollTop;
var perTick = difference / duration * 10;
setTimeout(function() {
scrollTop = scrollTop + perTick;
document.body.scrollTop = scrollTop;
document.documentElement.scrollTop = scrollTop;
if (scrollTop === to) return;
scrollTo(to, duration - 10);
}, 10);
}
平滑滚动现在在所有现代浏览器中都是默认实现的。 您还可以对其进行填充,以获得旧浏览器的支持。
// Scroll to specific values
// scrollTo is the same
window.scroll({
top: 2500,
left: 0,
behavior: 'smooth'
});
// Scroll certain amounts from current position
window.scrollBy({
top: 100, // could be negative value
left: 0,
behavior: 'smooth'
});
// Scroll to a certain element
document.querySelector('.hello').scrollIntoView({
behavior: 'smooth'
});
// Scroll certain amounts from current position for any element
document.querySelector('.scrollable-element').scrollBy({
top: 100,
behavior: 'smooth'
});
// Scroll to top
var element = document.querySelector('.scrollable-element');
element.scrollBy({
top: -element.scrollTop,
behavior: 'smooth'
});
来源:https://css-tricks.com/snippets/jquery/smooth-scrolling/