<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<script>
var s = "1+2"
var result = eval(s) //eval()直接让代码执行
alert(result)
var hh="2332+3443"
var result2=eval(hh)
var a = "哈哈哈"
var endcode = encodeURI(a)//字符编码
alert(endcode)
var decode = decodeURI(endcode)//字符解码
alert(decode)
var b = "10"
var c = parseInt(b) //只要出现不是数字的字符串就停止解析
alert(10 + b)
alert(10 + c)
var d = "ppp333jfjf"
var e = parseInt(d)
alert(parseFloat("10")) //parseFloat:解析小数
</script>
</body>
</html>