【Q622】Number.isNaN 与 globalThis.isNaN 有何区别

shfshanyue / Daily-Question

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Open shfshanyue opened 3 years ago

shfshanyue commented 3 years ago

Number.isNaN(NaN)
isNaN(NaN)

Number.isNaN('NaN')
isNaN('NaN')

nmsn commented 2 years ago

Number.isNaN(NaN)
isNaN(NaN)

Number.isNaN('NaN')
isNaN('NaN')

试了下 Number.isNaN('NaN') 是 false，其他都是 true

HydratedPig commented 1 year ago

还真没注意过，看了下 MDN，上面解释已经很明示了

isNaN:

Return Value: true if the given value is NaN after being converted to a number; otherwise, false.
Number.isNaN:

Return value: The boolean value true if the given value is a number with value NaN. Otherwise, false.

globalThis.isNaN 会对参数进行强制转换后判断是不是 NaN，而 Number.isNaN 不会对输入的参数进行强制转换