ant-design/components/_util/getScroll.tsx

export default function getScroll(target: any, top: boolean): number {
  if (typeof window === 'undefined') {
    return 0;
  }

  const prop = top ? 'pageYOffset' : 'pageXOffset';
  const method = top ? 'scrollTop' : 'scrollLeft';
  const isWindow = target === window;

  let ret = isWindow ? target[prop] : target[method];
  // ie6,7,8 standard mode
  if (isWindow && typeof ret !== 'number') {
    ret = window.document.documentElement![method];
  }

  return ret;
}