ASP.NET MVC 5中的下拉式填充错误

写你的 @Html.DropDownList 如下:

@Html.DropDownList("PlayerId", ViewBag.PlayerId as SelectList,"Select Player", htmlAttributes: new { @class = "form-control" })

现在它可以工作了!

你必须通过 SelectList 但实际上模型绑定器在 PlayerId 作为ViewModel属性和 游戏玩家 作为 ViewBag 属性,从而导致错误。

最好创建一个viewmodel属性来存储具有不同名称的选项列表:

public class ViewModel
{
    public int PlayerId { get; set; }

    // other properties

    // option list here
    public List<SelectListItem> PlayerList { get; set; }
}

然后将数据库中的选项列表添加到控制器操作中:

public ActionResult Create()
{
    var model = new ViewModel();
    model.PlayerList = db.Players.Select(x => new SelectListItem { Text = x.Name, Value = x.Id }).ToList();
    return View(model);
}

然后使用强类型助手绑定它:

@Html.DropDownListFor(model => model.PlayerId, Model.PlayerList, "Select", new { @class = "form-control" })

相关问题:

The ViewData item that has the key is of type 'System.Int32' but must be of type 'IEnumerable<SelectListItem>'