JavaScript Global method: isNaN()
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The JavaScript
Global
isNaN() method returns true if the value equates to NaN
(after initial conversion to a Number) otherwise returns false.
It
has the following syntax with the following parameters:
isNaN(x)
|
Parameter
|
Required / Optional
|
Description
|
|
x
|
Required
|
Input parameter
|
The Number.isNaN
method is subtly different to the global isNaN
function. The latter coerces a value to a number before testing it, whilst the
former does not. So, Number.isNaN("NaN")
returns false, whilst isNaN("NaN") returns true.
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