How to call codeigniter function through javascript function

How to call codeigniter function through javascript function

This is not working in my codeigniter function i have the id and cannot
get that id.Please help me. this is my view and i am trying to send my id
through the function.
<script type="text/javascript">
function makeajaxcall(id)
{
//alert(id);
var r=confirm("Do you want to Delete");
if (r==true)
{
window.location.href = "<?php echo
site_url('controller_d/login/admin_link_delete_user?id='.id);?>";
}
else
{
x="You pressed Cancel!";
alert(x);
}
}
</script>