这是代码 效果图在下面
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>20-test1</title>
<style type="text/css">
canvas{
animation-name: move;
animation-duration: 2s;
animation-iteration-count: infinite;
animation-timing-function: linear;
}
div{
width: 400px;
margin: 40px auto;
}
@keyframes move{
0%{
transform:rotate(0deg);
}
100%{
transform:rotate(360deg);
}
}
</style>
<script type="text/javascript">
window.onload=function(){
var canvas = document.getElementById(‘canvas‘)
var context = canvas.getContext(‘2d‘)
context.beginPath()
context.arc(200,200,200,Math.PI/2,Math.PI*3/2)
context.closePath()
context.fillStyle = ‘black‘
context.fill()
context.beginPath()
context.arc(200,200,200,Math.PI*3/2,Math.PI/2)
context.closePath()
context.fillStyle = ‘red‘
context.fill()
context.beginPath()
context.arc(200,100,100,0,Math.PI*2)
context.closePath()
context.fillStyle = ‘black‘
context.fill()
context.beginPath()
context.arc(200,300,100,0,Math.PI*2)
context.closePath()
context.fillStyle = ‘red‘
context.fill()
context.beginPath()
context.arc(200,100,10,0,Math.PI*2)
context.closePath()
context.fillStyle = ‘red‘
context.fill()
context.beginPath()
context.arc(200,300,10,0,Math.PI*2)
context.closePath()
context.fillStyle = ‘black‘
context.fill()
// context.rotate(180)
}
</script>
</head>
<body>
<div>
<canvas id="canvas" width="400px" height="400px"></canvas>
</div>
</body>
</html>
原文：https://www.cnblogs.com/bhba223/p/11558452.html