remove_elements_from_select.js

// This example will remove all Regions that are not "12" and all Municipalities not listed below.
var shipping_to = ["Cerrillos","Cerro Navia","Conchali","El Bosque","Estacion Central","Huechuraba","Independencia","La Cisterna","La Florida","La Granja","La Pintana","La Reina","Las Condes","Lo Barnechea","Lo Espejo","Lo Prado","Macul","Maipu","Ñuñoa","Padre Hurtado","Pedro Aguierre Cerda","PeÑAlolen","Providencia","Pudahuel","Puente Alto","Quilicura","Quinta Normal","Recoleta","Renca","San Bernardo","San Joaquin","San Miguel","San Ramon","Santiago Centro","Vitacura"]  

  function removeItems(select,shipping_to){
     $('#' + select +' option:not(:first)').filter(function() {
       return $.inArray($.trim($(this).text()), shipping_to) == -1;
     }).remove();
   };
  
  $("#order_shipping_address_region").change(function(){
    var interval = setInterval(function(){
      if($("#order_shipping_address_municipality").text()){
        removeItems("order_shipping_address_municipality",shipping_to);
        clearInterval(interval)
      }
    }, 500)
    });
  
  $(document).ready(function(){
    var interval = setInterval(function(){
      $("#order_shipping_address_region").val("12"); 
      if( $("#order_shipping_address_region").val() == "12"){
        clearInterval(interval)
        // fire native change event on select element -- START
        element = document.getElementById('order_shipping_address_region')
        var evt = document.createEvent("HTMLEvents");
        evt.initEvent("change", false, true);
        element.dispatchEvent(evt);
        // fire native change event on select element -- END
         removeItems("order_shipping_address_region",["Metropolitana"]);
      }
    }, 500)
    });