滾動條緩動滾回頂部事件
阿新 • • 發佈:2019-01-04
// 原生JS
window.onload
= function () {
document.getElementById("btn").onclick
= function () {
timer = setInterval(function () {
var scrollTop
= window.pageYOffset || document.documentElement.scrollTop
|| document.body.scrollTop
|| 0;
var speed
= -100;
if (scrollTop
== 0) {
clearInterval(timer);
}
// 相容寫法:
// document.documentElement.scrollTop = document.body.scrollTop = window.pageYOffset = scrollTop + speed;
document.body.scrollTop = scrollTop
+ speed;
}, 30)
}
}
// JQ 寫法
$(function () {
$("#btn").click(function(){
$('body,html').animate({scrollTop:0},1000);
return false;
});
});