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@@ -0,0 +1,59 @@
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+<!DOCTYPE html>
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+<html lang="en">
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+<head>
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+ <meta charset="UTF-8">
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+ <meta name="viewport" content="width=device-width, initial-scale=1.0">
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+ <title>Document</title>
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+</head>
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+<body>
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+ <script>
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+ // 基本数据类型
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+ var num = 1;
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+ var str = 'hello';
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+ var bool = true;
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+ var oNull = null;
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+ var oUndefined = undefined;
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+ // 引用数据类型
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+ var arr = [1,2,3,4,5];
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+ var obj = {};
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+ var foo = function(){};
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+
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+ // typeof 可以判断基本数据类型 返回字符串
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+ // console.log(typeof num);
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+ // console.log(typeof str);
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+ // console.log(typeof bool);
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+ // console.log(typeof oNull);
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+ // console.log(typeof oUndefined);
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+ // console.log(typeof arr);
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+ // console.log(typeof obj);
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+ // console.log(typeof foo);
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+
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+ // instanceof 可以判断引用数据类型 返回布尔值
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+ // console.log(arr instanceof Array);
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+ // console.log(obj instanceof Object);
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+ // console.log(foo instanceof Function);
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+ // console.log(num instanceof Number);
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+
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+ // cunstructor 可以判断引用数据类型 返回构造函数
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+ // Array, Object, Function, Number, String, Boolean
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+ // console.log(arr.constructor);
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+ // console.log(obj.constructor);
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+ // console.log(foo.constructor);
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+ // console.log(num.constructor);
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+ // console.log(str.constructor);
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+
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+ // Object.prototype.toString.call() 可以判断所有数据类型 返回字符串
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+ console.log(Object.prototype.toString.call(num));
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+ console.log(Object.prototype.toString.call(str));
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+ console.log(Object.prototype.toString.call(bool));
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+ console.log(Object.prototype.toString.call(oNull));
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+ console.log(Object.prototype.toString.call(oUndefined));
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+ console.log(Object.prototype.toString.call(arr));
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+ console.log(Object.prototype.toString.call(obj));
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+ console.log(Object.prototype.toString.call(foo));
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+
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+
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+
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+ </script>
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+</body>
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+</html>
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