2.6.Javascript--数值型 

<!DOCTYPE HTML>
<html lang="en-US">
<head>
    <meta charset="UTF-8">
    <title>数值型</title>
</head>
<body>
    <script type="text/javascript">
        
        var num = 1988;
        /*
        if(!isNaN(num)){
            document.write("非数值型");
        }
        */
        
        if(num.constructor == Number){
            document.write("数值型");
            document.write(typeof num.toString());
        }
        document.write("<br/>");
        document.write(Number.MAX_VALUE + "<br/>");
        document.write(Number.MIN_VALUE + "<br/>");
        
        var a = 10 ;
        var b = a++ ;//先执行再运算
var c = ++a ;//先运算再执行
        
        //document.write(a + "<br/>");
        document.write(b + "<br/>");
        document.write(c + "<br/>");
        
    </script>
</body>
</html>
posted @ 2012-03-14 16:29  校长阿四  阅读(180)  评论(0)  编辑  收藏  举报