Form validation in JAvascript with Regexp
- by Nikita Barsukov
I have a webpage with an input field where only digits are allowed.
The input field has an onkeyup event that starts this validating function:
function validate() {
var uah_amount = document.getElementById("UAH").value;
var allowed = /^\d+$/;
document.getElementById("error").innerHTML = document.getElementById("UAH").value;
if (!allowed.test(uah_amount)) {
document.getElementById("error").style.backgroundColor = "red";
}
}
Everything works as I expect until I hit Backspace button to remove some characters. In this case function always behaves as if I entered letters.
How to correct this?
