mui返回顶部按钮显示隐藏

//返回顶部按钮显示隐藏

var scrollToTopBox = document.getElementById('backTop');

window.addEventListener('scroll', function(e) {

if (window.pageYOffset >= 300){

scrollToTopBox.style.display="block";

}else if(window.pageYOffset <300){

scrollToTopBox.style.display="none";

}

});

返回顶部

scrollToTopBox.addEventListener('tap',function(e){

window.scrollTo(0, 0, 100);

})