<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>JS基础 热身课练习</title>
<style>
* {
margin: 0;
padding: 0;
}
body {
position: relative;
}
p {
padding: 20px;
margin-right: 20px;
}
#box {
width: 100px;
height: 100px;
border: 5px solid black;
margin-left: 20px;
}
#mask {
position: fixed;
height:100%;
width: 100%;
background: rgba(0, 0, 0, 0.4);
display: none;
}
#setting {
width: 350px;
height: 300px;
border: 10px solid gray;
background: white;
position: absolute;
bottom: 0;
right: 0;
}
.options {
padding: 20px;
}
.options span {
display: inline-block;
border: 1px solid black;
padding: 5px;
margin-left: 10px;
cursor: pointer;
}
#bgRed {
background: red;
}
#bgYellow {
background: yellow;
}
#bgGreen {
background: green;
}
.last {
text-align: center;
}
</style>
<script>
</script>
</head>
<body>
<div id="mask">
<div id="setting">
<div class="options" id="color">
选择背景：
<span id="bgRed" color="red">红</span>
<span id="bgYellow" color = "yellow">黄</span>
<span id="bgGreen" color="green">绿</span>
</div>
<div class="options" id="w">
选择宽度：
<span id="width200">200</span>
<span id="width300">300</span>
<span id="width400">400</span>
</div>
<div class="options" id = "h">
选择高度：
<span id="height200">200</span>
<span id="height300">300</span>
<span id="height400">400</span>
</div>
<div class="options last">
<span id="reset">恢复</span>
<span id="ok">确定</span>
</div>
</div>
</div>
<p>请为下面的div设置样式：<input id="set" type="button" value="点击设置样式"></p>
<div id="box"></div>
</body>
</html>
<script src="public.js"></script>
<script>
$id("set").onclick = function(){
$id("mask").style.display = "block";
}
$id("ok").onclick = function(){
$id("mask").style.display = "none";
}
//定义三个函数 设置颜色 设置宽度 设置高度
function setColor(color){
$id("box").style.backgroundColor = color;
}
function setWidth(width){
$id("box").style.width = width + "px";
}
function setHeight(height){
$id("box").style.height = height + "px";
}
var colorSpan = $id("color").children;
for( var i = 0 ; i < colorSpan.length ; i++ ){
colorSpan[i].onclick = function(){
setColor( this.getAttribute("color") );
}
}
var widthSpan = $id("w").children;
for( var i = 0 ; i < widthSpan.length ; i++ ){
widthSpan[i].onclick = function(){
setWidth( this.innerHTML );
}
}
var heightSpan = $id("h").children;
for( var i = 0 ; i < heightSpan.length ; i++ ){
heightSpan[i].onclick = function(){
setHeight( this.innerHTML );
}
}
$id("reset").onclick = function(){
setColor("transparent");
setWidth(100);
setHeight(100);
}
</script>
原文地址：https://www.cnblogs.com/tis100204/p/10319264.html