Question

I am trying to have a clientside check, if an entered value:

• is a valid email address
• has the right domain name

I came up with following code, but it doesn’t work:

var userinput = '[e-mail]';
var domain = 'somethingelse.com';
domain.replace('.', '\.');
var pattern = new RegExp('/^[a-zA-Z0-9._-]+@' + domain + '$/');
if(!pattern.test(userinput))
{
    alert('not a valid email address, or the wrong domain!');
}

Answer 1

Do it in two steps. First, use a regex like James recommends to test for a valid(ish) e-mail address. Second, make sure the domain matches the allowed domain as Siva suggests.

var userinput = '[e-mail]';
var domain = 'somethingelse.com';

var pattern = /^\b[A-Z0-9._%-]+@[A-Z0-9.-]+\.[A-Z]{2,4}\b$/i
if(!pattern.test(userinput) || userinput.split('@')[1] != domain)
{
  alert('not a valid email address, or the wrong domain!');
}​

You can fiddle with it here.