javascript - Why does isNaN(" ") equal false -


I have a quick question (I hope!). In JS, why do isNaN ("") wrong, but evaluate to isNa ("x") correct?

I am performing numeric actions on the text input field, and checking that the field is empty, "", or NaN, when a person finds a handful of spaces in the area, then my The validation fails in all three, and I am confused about why this isNAN has been investigated.

Thank you!

Javascript interprets an empty string as a 0, which then fails in the ISNAN test is. You can use parseInt on the string which will not convert an empty string to 0. The result should be unsuccessful. NAN


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