Change the value of an hidden field with radio button

Hello,

I have a form with an hidden field (submit_to). This hidden field is an email address to which the form is sent. This field is mandatory.

I need that the form is sent to the email address defined with radio buttons.

I have 3 radio buttons:
- USA
- UK
- USA + UK

Now, if someone selects the USA button, then the form should be sent to usa@test.com. If the UK is checked, the email should be sent to uk@test.com and if the third option is checked, then the email should be sent to both email addresses.

Could you please help me?

Thanks

<input type="radio" name="country" onClick="document.forms[0].action='mailto:'+document.country.value+'@test.co m'">

Something like that, though I wouldn't guess that'll work without some adjustments. I don't know about the emailing to 2 addresses unless by using a server-side script.