JavaScript uses the isNaN () function to determine whether a variable is a digital _javascript technique

Source: Internet
Author: User
Tags numeric value
In JavaScript, the method of determining whether a variable is a number is mainly about the isNaN () function in JavaScript.

Function:

The isNaN () function checks whether its arguments are non-numeric values.

Grammar:

isNaN (x) x is required. The value to be detected.

return value:

If X is a special non-numeric value NaN (or can be converted to such a value), the returned value is true. Returns False if X is a different value.

Description

The isNaN () function can be used to determine whether its argument is NaN, which represents an illegal number (such as the result of being 0 apart).
If the result of Nan being compared to any value (including itself) is false, you cannot use the = = or = = operator to determine whether a value is NaN. Because of this, the isNaN () function is required.
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