<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<script type="text/javascript">
var screenwidth=window.screen.width;
var screenheight=window.screen.height;
document.write(`
设备像素比:${window.devicePixelRatio},
屏幕的宽度为:${screenwidth},
屏幕的高度为:${screenheight}
`)
</script>
</body>
</html>