描述：当用打开页面的时候显示当前的日期。
实例代码:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>模拟日历</title>
</head>
<style>
.time{
width: 1200px;
margin: 200px auto;
color: red;
text-align: center;
font: 600 30px/30px "simsun";
}
</style>
<body>
<div class="time"></div>
</body>
</html>
<script>
var date = new Date();
var year = date.getFullYear();
var month = date.getMonth();
var day = date.getDate();
var week = date.getDay();
var arr = ["星期日","星期一","星期二","星期三","星期四","星期五","星期六"];
var time = document.getElementsByClassName("time")[0];
time.innerText = "今天是"+year+"年"+(month+1)+"月"+day+"日，"+arr[week];
</script>