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@@ -0,0 +1,55 @@
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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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+ var arr = [1,2,3,4];
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+ var obj = {
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+ name:"Lucy",
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+ age:10
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+ }
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+ var fn1 = function() {
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+ console.log("你好")
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+ }
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+ // 1.typeof
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+ console.log(typeof 1);//number
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+ console.log(typeof "1"); //string
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+ console.log(typeof true); //boolean
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+ console.log(typeof undefined); //undefined
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+ console.log(typeof null); //object
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+ console.log(typeof arr);//object
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+ console.log(typeof obj);//object
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+ console.log(typeof fn1);//function
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+
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+
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+ // 2.instanceof
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+ console.log(obj instanceof Object);
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+ console.log(arr instanceof Object);
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+ console.log(fn1 instanceof Object);
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+
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+ // 3.Object.prototype.toString.call()
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+ console.log(Object.prototype.toString.call(1));
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+ console.log(Object.prototype.toString.call("哈哈"));
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+ console.log(Object.prototype.toString.call(false));
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+ console.log(Object.prototype.toString.call(null));
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+ console.log(Object.prototype.toString.call(undefined));
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+ console.log(Object.prototype.toString.call(obj));
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+ console.log(Object.prototype.toString.call(arr));
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+ console.log(Object.prototype.toString.call(fn1));
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+
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+ // 4.constructor 构造器 无法校验null 和 undefined
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+ console.log((1).constructor === Number);
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+ console.log("哈哈".constructor === String);
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+ console.log(false.constructor === Boolean);
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+ // console.log(null.constructor === Object);
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+ // console.log(undefined.constructor === undefined);
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+ console.log(obj.constructor === Object);
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+ console.log(arr.constructor === Object);
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+ console.log(fn1.constructor === Object);
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+ </script>
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+</body>
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+</html>
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