js滚动到页面顶部

// 页面滚动到顶部
// 方法一
document.body.scrollTop=document.documentElement.scrollTop=0
// 方法二
document.body.scrollIntoView()

// scrollIntoView 是元素也有的方法, 可以用在页面元素上，例如
document.getElementById('id').scrollIntoView()

//回到顶部
const scrollToTop = () => {undefined
const fromTopDistance = document.documentElement.scrollTop || document.body.scrollTop;
if (fromTopDistance > 0) {undefined
window.requestAnimationFrame(scrollToTop);
window.scrollTo(0, fromTopDistance - fromTopDistance/ 8);
}
}
//执行此方法
scrollToTop()

$(".scroll").click(function(event)
{
  //prevent the default action for the click event
  event.preventDefault();
  //get the full url - like mysitecom/index.htm#home
  var full_url = this.href;
  //split the url by # and get the anchor target 
  //name - home in mysitecom/index.htm#home
  var parts = full_url.split("#");
  var trgt = parts[1];
  //get the top offset of the target anchor
  var target_offset = $("#"+trgt).offset();
  var target_top = target_offset.top;
  //goto that anchor by setting the body scroll top to anchor top
  $('html, body').animate({scrollTop:target_top}, 500);
});​

$('.scroll_top').click(function(){$('html,body').animate({scrollTop: '0px'}, 800);});

$('.scroll_a').click(function(){$('html,body').animate({scrollTop:$('.a').offset().top}, 800);});

element.scrollTo(x-coord, y-coord);
//或者
element.scrollTo(options)

element.scrollTo(0, 1000);
//ScrollToOptions
element.scrollTo({
  top: 100,
  left: 100,
  behavior: 'smooth'
});