首頁猿問 JSON.stringify(Na...

JSON.stringify(NaN)為什么等于null

JavaScript

九州編程 2019-03-14 21:57:45

JSON.stringify(NaN)"null"JSON.stringify([NaN])"[null]"JSON.stringify(undefined)undefinedJSON.stringify(null)"null"JSON.stringify([undefined])"[null]"求解釋原理

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2 回答

躍然一笑

TA貢獻(xiàn)1826條經(jīng)驗獲得超6個贊

從ecma-262 規(guī)范文檔的角度解釋標(biāo)題的問題就非常簡單。

直接看為什么 JSON.stringify(NaN) => "null"

NOTE 4
Finite numbers are stringified as if by calling ToString(number). NaN and Infinity regardless of sign are represented as the String null.

NaN 會被當(dāng)成字符串 null

為什么
JSON.stringify(undefined) => undefined
JSON.stringify([undefined]) => "[null]"

NOTE 5
Values that do not have a JSON representation (such as undefined and functions) do not produce a String. Instead they produce the undefined value. In arrays these values are represented as the String null

反對回復(fù) 2019-03-14