public class TestDDLController : Controller { public IActionResult Index() { return View(); } [HttpPost] public JsonResult GetCategory(string id) { List category = new List(); switch (id) { case "1": category.Add(new SelectListItem { Text = "N/A", Value = "N/A" }); break; case "2": category.Add(new SelectListItem { Text = "N/A", Value = "N/A" }); break; case "3": category.Add(new SelectListItem { Text = "N/A", Value = "N/A" }); break; case "4": category.Add(new SelectListItem { Text = "---Select---", Value = null }); category.Add(new SelectListItem { Text = "Address", Value = "Address" }); category.Add(new SelectListItem { Text = "Closing", Value = "Closing" }); break; } return Json(new SelectList(category, "Value", "Text")); } }