前端 - js 图片懒加载

Question

有一个手机页面，有很多屏图片，我们向下滚动，从第一屏滚到最后一屏，第一屏和最后一屏的图片会加载出来，但第一屏和最后一屏之间的图片不让加载出来，各们大神，不知道有什么方法可以实现？

Answer 1

This just requires setting a delay, commonly known as function throttling. That is, when a scroll event occurs, the image is not loaded immediately, but is delayed for a while. If there is a new scroll event during this period, the loading action of the previous event will be canceled.

Answer 2

Detect the distance between the top of the image container and the top of the browser window (if(offsetTop＜0){**}). The computer is not nearby, so I don’t have an example for you. Please help me write it down.