<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><title>Title</title><style>* {margin: 0;padding: 0;}#div1 {width: 100px;height: 100px;background-color: red;position: absolute;left: 600px;top: 50px;}#div2 {width: 1px;height: 300px;position: absolute;left: 300px;top: 0;background-color: black;}</style><script>function startMove() {var oDiv = document.getElementById(\'div1\');setInterval(function () {var speed = (300 - oDiv.offsetLeft) / 10;//speed = Math.ceil(speed);//向上取整speed = speed > 0 ? Math.ceil(speed) : Math.floor(speed);//判断是否大于0， 向上or向下取整；oDiv.style.left = oDiv.offsetLeft + speed + \'px\';document.title = oDiv.offsetLeft + \',\' + speed;}, 30);}</script></head><body><input type="button" value="开始运动" onclick="startMove()"><div id="div1"></div><div id="div2"></div></body></html>