This form is search form. when I click the \"alfamart\" or \"bca\", I want the link change.
like this, link: /en2/maps(alfamart)or(bca)/
You don't need to get value from URL, you can change form action by select box value.
$('.selectpicker').change(function(){
if($(this).val() == 'alfamart'){
$('form').attr('action','alfamart.html');
alert('action is alfamart.html');
} else {
$('form').attr('action','BCA.html');
alert('action is BCA.html');
}
});