只允许以两种形式选中一个单选按钮

Question

I have two forms with one radio button for each form. How can I fix so that only one radio button can be checked at a time when multiple forms are involved?

Here are the essential parts of the two forms:

<form name="form1" action="http://www.my-site.com/go-here.php" method="post">
  <input type="radio" name="payment" value="radio1" checked="checked" /> Use form1
</form>

<form name="form2" action="http://www.my-site.com/instead-go-here.php" method="post">
  <input type="radio" name="payment" value="radio2" /> Use form2
</form>

Answer 1

HTML:

<form name="form1" action="http://www.my-site.com/go-here.php" method="post">
  <input type="radio" name="payment" value="radio1" /> Use form1
</form>

<form name="form2" action="http://www.my-site.com/instead-go-here.php" method="post">
  <input type="radio" name="payment" value="radio2" /> Use form2
</form> 

JavaScript:

$("[name=payment]").on("click",function(){

    $("[name=payment]").prop('checked', false)
    $(this).prop('checked', true)

});

Fiddle: http://jsfiddle.net/44mycngy/