javascript变量，类型第9节

1、变量，数据类型
<html>
<head>
    <title>变量</title>
</head>
<body>
    <h3>变量 数据类型</h3>
    <script type="text/javascript">
        var i = 10;
        var k = 20;
        var d = new Date();
        document.write("i = " + i + "<br/>");
        document.write("d = " + d + "<br/>");
        i = new Object();
        document.write("i = " + i + "<br/>");
        i = new Array(10,20,30);
        document.write("i = " + i + "<br/>");
        j = k +20;
        document.write("j = " + j + "<br/>");
        var name = '张三';//字符串不区分",'
        document.write("name = " + name + "<br/>");
        var sex = '男';
        document.write("sex = " + sex + "<br/>");
        var married= false;
        var test;
        document.write("test = " + test + "<br/>");
        test = null;
        document.write("test = " + test + "<br/>");
        var obj = new Object();
        document.write("obj = " + obj + "<br/>");
    </script>
　　<h3>2.检测变量的数据类型</h3>
　　<script type="text/javascript">
　　　　document.write("obj的类型 " + (typeof obj) + "<br/>");
　　　　document.write("test:" + (typeof obj) + "<br/>");
　　　　document.write("name 的类型" + (typeof name) +"<br/>");
　　　　document.write("sex 的类型" + (typeof sex) + "<br/>");
　　　　document.write("j :" + (typeof j) +"<br/>");
　　　　document.write("married " + (typeof married ) + "<br/>");
　　　　document.write("i 的类型 " + (typeof i) + "<br/>");
　　　　document.write("i:" , i instanceof Array,"<br/>");
　　　　document.write("i:", i instanceof Date,"<br/>");
　　</script>
　　<h3>3、运算符</h3>
　　<script type="text/javascript">
　　　　var a = 5;
　　　　var b = 3;
　　　　document.write("5 /3 = ",5/3,"<br/>");
　　　　document.write("8 / 2 = ",8/2,"<br/>");
　　</script>
</body>
</html>
结果：
javascript变量，类型 第9节

javascript变量，类型第9节
