首頁猿問 JavaScript typeof()

JavaScript typeof()

JavaScript

蝴蝶不菲 2019-07-16 09:09:15

typeof()這個函數(shù)是干什么用的？有幾個參數(shù)，每個參數(shù)代表什么？

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3 回答

月關寶盒

TA貢獻1772條經(jīng)驗獲得超5個贊

寫了代碼測試了下
<script>
document.write ("typeof(1): "+typeof(1)+" ");
document.write ("typeof(NaN): "+typeof(NaN)+" ");
document.write ("typeof(Number.MIN_VALUE): "+typeof(Number.MIN_VALUE)+" ")
document.write ("typeof(Infinity): "+typeof(Infinity)+" ")
document.write ("typeof(\"123\"): "+typeof("123")+" ")
document.write ("typeof(true): "+typeof(true)+" ")
document.write ("typeof(window): "+typeof(window)+" ")
document.write ("typeof(document): "+typeof(document)+" ")
document.write ("typeof(null): "+typeof(null)+" ")