lovecoding
/
W0407


			
				
					
						
						
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							<!DOCTYPE html>
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    <meta charset="UTF-8">
    <meta name="viewport" content="width=xw, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        /**
         * js基本数据类型
         * string number boolean undefined null
         * 
         * 引用数据类型 Object
         * object array function
         * 
         * 
         * typeof判断数据类型
         * null 会判断为object
        */

        console.log(typeof(1));
        console.log(typeof("1"));
        console.log(typeof(false));
        console.log(typeof(undefined));
        console.log(typeof(null));
        var a = {
            a:"你好"
        };
        var b = [1,2,34];
        var c = function() {
            console.log("你好")
        };
        console.log(typeof(a));
        console.log(typeof(b));
        console.log(typeof(c));

        if(null == undefined) {
            console.log("你好")
        } else {
            console.log("大家好")
        }
        /**
         * = 赋值
         * == 相等 强制转换类型
         * === 全相等 类型和值必须全部相等
        */
    </script>
</body>
</html>