regular expression in javascript which allows backspace

Question

My regular expression which allows characters, numbers, dot and underscore is

var numericReg = /^[a-zA-Z0-9\._]+$/;

How could i allow backspace in this reg ex.?

Answer 1

You can use [\b] to match backspace. So, just add it to your character class: -

var numericReg = /^[a-zA-Z0-9._\b]+$/;

Note that you don't need to escape dot (.) in character class. It has not special meaning in there.

See also: -

• http://www.regular-expressions.info/reference.html

for more escape sequences, and patterns in Regex.