<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>生成随机大小，颜色，位置的小球</title>
<style>
.btn {
width: 80px;
height: 20px;
text-align: center;
line-height: 20px;
border-radius: 6px;
background-color: #eeee;
cursor: pointer;
}
.app {
width: 1000px;
height: 800px;
border: 1px solid red;
border-radius: 12px;
position: relative;
}
.boo {
display: inline-block;
border-radius: 50%;
position: absolute;
}
</style>
</head>
<body>
<div class="btn">创建小球</div>
<div class="app"></div>
<script>
class Boo {
constructor() {
this.init()
}
init() {
// 创建一个小球
// 小球大小随机,背景色随机，位置随机
this.createBol()
}
getRandomWidthHeight() {
return Math.floor(Math.random() * 51);
}
getRandomLeft() {
return Math.round(Math.random()*999+1);
}
getRandomTop() {
return Math.round(Math.random()*799+1);
}
getRandomRgb() {
let r = Math.floor(Math.random()*256)
let g = Math.floor(Math.random()*256)
let b = Math.floor(Math.random()*256)
let rgb = `rgb(${r},${g},${b})`
return rgb
}
createBol() {
let app = document.getElementsByClassName('app')[0]
let boo = document.createElement('span')
let wh = this.getRandomWidthHeight() + 'px'
boo.style.width = wh
boo.style.height = wh
boo.className='boo'
boo.style.backgroundColor = this.getRandomRgb()
boo.style.left= this.getRandomLeft() + 'px'
boo.style.top= this.getRandomTop() + 'px'
app.append(boo)
}
}
let btn = document.getElementsByClassName('btn')[0]
btn.addEventListener('click', function () {
let boo = new Boo(20, 30)
})
</script>
</body>
</html>
创建随机大小的数字
Math.round(Math.random()*（max-min）+min);
创建随机背景色
getRandomRgb() {
let r = Math.floor(Math.random()*256)
let g = Math.floor(Math.random()*256)
let b = Math.floor(Math.random()*256)
let rgb = `rgb(${r},${g},${b})`
return rgb
}
