Create "mailto" element with variables

Question

I want to create a mailto href element which includes variables for subject and body. How do I manage to do that? I imagined something like this:

var mail = 'name@domain.com'
var subject = 'Welcome to ...'
var body = 'Dear Applicant,...'

<a href="mailto:mail?subject=subject&amp;body=body.">Send email</a>

Thanks for your help.