var packageSrc = new Object(); function selectPackageSource(field, city){ var cities = packageSrc[city]; if(typeof (cities) != 'undefined') { field.length = cities.length + 1; for (var i = 1; i < field.length; i++) { var city_arr = cities[i-1].split("|"); field[i].value = city_arr[0]; field[i].text = city_arr[1]; } field[0].value = -1; field[0].text = "-- ALL --"; field.selectedIndex = 0; } else { field.length = 0; } }