获取DropDownList的选定值。 Asp.NET MVC
我正在尝试填充DropDownList并在提交表单时获取所选值:
这是我的模型:
public class Book { public Book() { this.Clients = new List(); } public int Id { get; set; } public string JId { get; set; } public string Name { get; set; } public string CompanyId { get; set; } public virtual Company Company { get; set; } public virtual ICollection Clients { get; set; } }
我的控制器:
[Authorize] public ActionResult Action() { var books = GetBooks(); ViewBag.Books = new SelectList(books); return View(); } [Authorize] [HttpPost] public ActionResult Action(Book book) { if (ValidateFields() { var data = GetDatasAboutBookSelected(book); ViewBag.Data = data; return View(); } return View(); }
我的表格:
@using (Html.BeginForm("Journaux","Company")) { @Html.DropDownList("book", (SelectList)ViewBag.Books)
}
单击时,Action中的参数’book’始终为null。 我究竟做错了什么?
在HTML中,下拉框仅发送简单的标量值。 在您的情况下,这将是所选书籍的ID:
@Html.DropDownList("selectedBookId", (SelectList)ViewBag.Books)
然后调整您的控制器操作,以便从将传递给控制器操作的ID中检索该书:
[Authorize] [HttpPost] public ActionResult Action(string selectedBookId) { if (ValidateFields() { Book book = FetchYourBookFromTheId(selectedBookId); var data = GetDatasAboutBookSelected(book); ViewBag.Data = data; return View(); } return View(); }
您可以使用DropDownListFor,如下所示,它更简单
@Html.DropDownListFor(m => m.Id, new SelectList(Model.Books,"Id","Name","1"))
(你需要一个强类型视图 – View包不适合大型列表)
public ActionResult Action(Book model) { if (ValidateFields() { var Id = model.Id; ...
我认为这更容易使用。