Question

I have an array of numbers. The array may contain a zero.

How can I check if the array contains a number or not? I am currently doing that:

if (Number(arr. value(pos)) != false)

This however, considers 0 as false too. So if a 0 is in the array, it will consider it as if the array was empty.

How can I overcome this?

Answer 1

Try this:

if (Number(arr. value(pos)) !== false)

!= does a “falsy” check. 0, undefined, false, null, '', and NaN are all falsy. Everything else is “truthy”. If you want to test for false only (and not all other falsy statements) you have to use === or !==. Try to avoid != and ==, because most if the time you actually mean !== and ===