Need to dynamically change the form action depending on radio button selected

[brazenmedia]

I need to change the form action depending on which radio button is selected. The catch here is that the form action is using mailto: with an encoding type. I can successfully change the action, but it does not retain the enctype, therefore it does not post the form to the email client. Really all I want to change is the subject part of the mailto line.

So I have 3 different options for the action line, depending on which is selected for the radio button, that is the one that will submit and create a customized subject line:

<form method="post" action="mailto:mail@mail.com?subject=Subject1" enctype="text/plain" name="Subject1">

<form method="post" action="mailto:mail@mail.com?subject=Subject2" enctype="text/plain" name="Subject2">

<form method="post" action="mailto:mail@mail.com?subject=Subject3" enctype="text/plain" name="Subject3">

Best way to handle this with javascript?

[hexburner]

Does a form even work with action mailto:mail@mail.com?subject=Subject ?
I don't think it would, but here's how to proceed with what you're doing.

function changeAction(radio) {
    radio.form.setAttribute('action', radio.value);
}

<input type="radio" onchange="changeAction(this);" value="mailto:mail@mail.com?subject=Subject1"/> Subject 1
<input type="radio" onchange="changeAction(this);" value="mailto:mail@mail.com?subject=Subject2"/> Subject 2
<input type="radio" onchange="changeAction(this);" value="mailto:mail@mail.com?subject=Subject3"/> Subject 3