JavaScript - Test for an integer

Question

I have a text field that allows a user to enter their age. I am trying to do some client-side validation on this field with JavaScript. I have server-side validation already

Answer 1

If your number is in the 32bit integer range, you could go with something like:

function isInt(x) { return ""+(x|0)==""+x; }

The bitwise or operator forces conversion to signed 32bit int. The string conversion on both sides ensures that true/false want be matched.