# Number.isNaN 与 globalThis.isNaN 有何区别

Issue

欢迎在 Gtihub Issue 中回答此问题: Issue 640 (opens new window)

Author

Number.isNaN(NaN);
isNaN(NaN);

Number.isNaN("NaN");
isNaN("NaN");

Author

Number.isNaN(NaN);
isNaN(NaN);

Number.isNaN("NaN");
isNaN("NaN");

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

Author

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