Set value in radio button

I have to set value of radio field name “release” with the help if java script ,and my code is

var answer =confirm(“Are you releasing the document??”)

if (answer)

{

alert("ok");

//(document.forms(0).release.checked=“Released”)

document.forms(0).release.options(document.forms(0).release.selectedIndex).text=“Released”;

in radio field there is two option first:- Released";

second :- draft

here alert message prompt but value does not set.

Please help me its urgent

Subject: set value in radio button

document.forms[0].release[0].checked = true

will do the trick