js代替 scrolltop

// 获取整个文档的滚动位置
const scrollPosition = window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop;

// 获取某个元素的滚动位置
const element = document.getElementById('myElement');
const elementScrollPosition = element.scrollTop;

// 滚动到页面顶部
window.scrollTo(0, 0);

// 滚动到页面指定位置
window.scrollTo(0, 500); // 滚动到垂直位置 500px

// 平滑滚动到页面顶部
window.scrollTo({ top: 0, behavior: 'smooth' });

// 平滑滚动到页面指定位置
window.scrollTo({ top: 500, behavior: 'smooth' });

// 滚动某个元素到指定位置
const element = document.getElementById('myElement');
element.scrollTo(0, 500); // 滚动到垂直位置 500px

function smoothScrollTo(targetPosition, duration) {
  const startPosition = window.pageYOffset;
  const distance = targetPosition - startPosition;
  let startTime = null;

  function animation(currentTime) {
    if (startTime === null) startTime = currentTime;
    const timeElapsed = currentTime - startTime;
    const run = ease(timeElapsed, startPosition, distance, duration);
    window.scrollTo(0, run);
    if (timeElapsed < duration) requestAnimationFrame(animation);
  }

  function ease(t, b, c, d) {
    t /= d / 2;
    if (t < 1) return c / 2 * t * t + b;
    t--;
    return -c / 2 * (t * (t - 2) - 1) + b;
  }

  requestAnimationFrame(animation);
}

smoothScrollTo(500, 1000); // 平滑滚动到垂直位置 500px，持续时间为 1000ms

const scrollPosition = window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop;