alert(1/0)提醒Infinity和alert(1 / -0)警报-Infinity. alert(-1 / -0)提醒Infinity,正如我在使用实数进行一些操作时所预期的那样.我不能说无穷大是一个可衡量的价值. javascript是否认为它是一些数字？

解决方法:

是的,Infinity和-Infinity是special values of the Number type.根据ES5规范：

There are two other special values, called positive Infinity and negative Infinity. For brevity, these values are also referred to for expository purposes by the symbols +∞ and −∞, respectively. (Note that these two infinite Number values are produced by the program expressions +Infinity (or simply Infinity) and -Infinity.)

另请注意,NaN也是Number类型的值,尽管它是“not a number”的首字母缩写词.