下拉选择未被清除

我试图从下拉列表中清除所选的值,但该值仍然存在。这是同样的行为使用 @Html.DropDownListFor

控制器

public class HomeController : Controller
{

    [Route("/Home/Index")]
    [Route("/Home/Index/{Category}")]
    [Route("/Home/Index/{Category}/{Type}")]
    public IActionResult Index(HomeModel model)
    {
        // Issue is here
        // for url: home/index/accessories/test
        // "Category" is cleared if it is not valid "type"
        // but still "Accessories" remains selected in the drop down
        if (model.Type != "Electronics" && model.Type != "Furniture")
        {
            model.Category = string.Empty;
        }

        return View(new HomeModel() { Category = model.Category, Type = model.Type });
    }

@model WebApplication1.Controllers.HomeModel

<select asp-for="Category" asp-items="@Model.Categories"></select>
<select asp-for="Type" asp-items="@Model.Types"></select>

模型

public class HomeModel
{
    public string Category { get; set; }

    public string Type { get; set; }

    public List<SelectListItem> Categories { get; set; } = new List<SelectListItem>
    {
        new SelectListItem() { Text="Computers & Laptops", Value="Computers-Laptops" },
        new SelectListItem() { Text="Accessories", Value="Accessories" },
    };

    public List<SelectListItem> Types { get; set; } = new List<SelectListItem>
    {
        new SelectListItem() { Text="Electronics", Value="Electronics" },
        new SelectListItem() { Text="Furniture", Value="Furniture" },
    };
}

更新

 <select asp-for="Category" asp-items="@Model.Categories">
        <option value="">Select Category</option>
 </select>