JS中的电话号码输入掩码

Question

I'm trying to figure out where the number 1 comes from (in the example below you write any phone number and press Backspace many times). Can you please tell me what is wrong in this code?

 const input = document.querySelector('input[name="phone"]'); input.addEventListener('input', function () { let x = input.value; x = x.replace(/^\\+1 /, ''); x = x.replace(/\\D/g, '').match(/(\\d{0,3})(\\d{0,3})(\\d{0,2})(\\d{0,2})/); x = !x[2] ? x[1] : x[1] + ' ' + x[2] + (x[3] ? `-${x[3]}` : '') + (x[4] ? `-${x[4]}` : ''); x = x.startsWith('+1 ') ? x : '+1 ' + x; input.value = x; });

 <input name="phone" placeholder="Phone number">

Answer 1

You need remove it on your code.

phone = phone.replace(/^\+1 /, '')

Also:

phone = phone.startsWith('+1 ') ? phone : '+1 ' + phone;

Answer 2

You had to replace the line:

x = x.replace(/^\+1 /, '');

to:

x = x.replace(/^\+1/, '');

(remove the space)