JavaScript typeof 操作符

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<title>菜鸟教程(runoob.com)</title>
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typeof 操作符返回变量、对象、函数、表达式的类型。

<script>
document.getElementById("demo").innerHTML =
typeof "john" + " " +
typeof 3.14 + " " +
typeof NaN + " " +
typeof false + " " +
typeof [1,2,3,4] + " " +
typeof {name:'john', age:34} + " " +
typeof new Date() + " " +
typeof function () {} + " " +
typeof myCar + " " +
typeof null;
</script>

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