<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script>
//1.将js封装成函数，点击某按钮时调用
//2.不把js封装成函数，直接在此处写js，则网页加载时直接调用
//该js的执行时机设置比body还早.
// alert(1);
console.log("控制台打印");
//1.声明变量
var x;
console.log(x);
x=3;
console.log(x);
var y="hello";
console.log(y);
//2.隐式转换
var s="hi";
var n=3.14;
var b=true;
console.log(s+n);
console.log(s+b);
console.log(n+b);
console.log(b+b);
//3.强制转换
console.log(n.toString()+1);
console.log(parseInt(n));
console.log(parseInt("5.6"));
console.log(parseInt("abc"));
console.log(parseInt(5.6));
console.log(parseFloat(5.6));
console.log(typeof(n));//查看变量类型
console.log(isNaN("abc"));//是否判断参数是不是“不是一个数”
</script>
</head>
<body>
<p>js语法和java十分相似</p>
</body>
</html>
原文：http://www.cnblogs.com/Bighua123/p/7624246.html