How to disallow certain characters in input?

Question

JavaScript

In input number now you can enter "+", "-", "." how can it be banned? Maybe a regular expression

Answer 1

By event , "input"replace valuewith a positive integer value:

Newans: remember the previous valid value, so that, if anything, if NaN, do not reset the field, but return to the last normal one.

Answer 2

Answer 3

htmlbook.ru/html/input/pattern