<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title></title> <style> div { width: 300px; height: 300px; background-color: pink; } </style> <script> //随机产生一个发6进制的颜色值 //封装成一个函数 console.log(parseInt(Math.random() * 5)); function getColor() { var str = "#"; var arr = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f"]; for (var i = 0; i < 6; i++) { //产生的每一个随机数都是一个索引,根据索引找到数组中对应的值,拼接到一块儿 str += arr[parseInt(Math.random() * 16)]; } return str; } //页面记载的事件 window.onload = function () { //在文档中经过id的属性值查找这个元素(标签).设置该标签的背景颜色 document.getElementById("dv").style.backgroundColor = getColor(); }; // alert(getColor()); </script></head><body> <div id="dv"> </div></body></html>