案例：javascript案例     状态：可编辑再运行    进入竖版
 运行结果　
​x
 
1
<html>
2
<head>
3
<script type="text/javascript">
4
function displaynum()
5
{
6
var num = new Number(10000);
7
alert(num.toExponential(1))
8
}
9
</script>
10
</head>
11
<body>
12
​
13
Show the number 10,000 as an exponential notation:
14
​
15
<form>
16
<input type="button" value="Show!" onclick="displaynum()" >
17
</form>
18
​
19
</body>
20
</html>
21
​