asp.net-mvc-3 - MVC3 下拉列表显示每个项目的多个属性

Question

我希望在我的 View 中有一个下拉列表，显示患者的 ID、名字和姓氏。使用下面的代码，它会显示每个患者的名字。如何将所有三个属性传递到 View 袋中并让它们显示在下拉列表中？

Controller

public ActionResult Create()
            {ViewBag.Patient_ID = new SelectList(db.Patients, "Patient_ID", "First_Name");
             return View();
            } 

查看

    <div class="editor-field">
                @Html.DropDownList("Patient_ID", String.Empty)
                @Html.ValidationMessageFor(model => model.Patient_ID)
            </div>

谢谢。

好的，我已按如下方式编辑了代码，但收到错误“不存在具有键“SelectedPatientId”的“IEnumerable”类型的 ViewData 项。”

Controller


    public ActionResult Create()
            {
                var model = new MyViewModel();

        {
             var Patients = db.Patients.ToList().Select(p => new SelectListItem
            {
                Value = p.Patient_ID.ToString(),
                Text = string.Format("{0}-{1}-{2}", p.Patient_ID, p.First_Name, p.Last_Name)
            });

            var Prescribers = db.Prescribers.ToList().Select(p => new SelectListItem
    {
        Value = p.DEA_Number.ToString(),
        Text = string.Format("{0}-{1}-{2}", p.DEA_Number, p.First_Name, p.Last_Name)
    });

            var Drugs = db.Drugs.ToList().Select(p => new SelectListItem
            {
                Value = p.NDC.ToString(),
                Text = string.Format("{0}-{1}-{2}", p.NDC, p.Name, p.Price)
            });


        };
                return View(model);
            }

View Model

    public class MyViewModel
        {
            [Required]
            public int? SelectedPatientId { get; set; }
            public IEnumerable<SelectListItem> Patients { get; set; }

            [Required]
            public int? SelectedPrescriber { get; set; }
            public IEnumerable<SelectListItem> Prescribers { get; set; }

            [Required]
            public int? SelectedDrug { get; set; }
            public IEnumerable<SelectListItem> Drugs { get; set; }
        }

查看

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)

     @Html.DropDownListFor(
        x => x.SelectedPatientId,
        Model.Patients,
        "-- Select patient ---"
    )
    @Html.ValidationMessageFor(x => x.SelectedPatientId)
    <button type="submit">OK</button>

         @Html.DropDownListFor(
        x => x.SelectedPrescriber,
        Model.Patients,
        "-- Select prescriber ---"
    )
    @Html.ValidationMessageFor(x => x.SelectedPrescriber)
    <button type="submit">OK</button>
}

Answer 1

我建议您根本不要使用任何ViewBag并定义 View 模型:

public class MyViewModel
{
    [Required]
    public int? SelectedPatientId { get; set; }
    public IEnumerable<SelectListItem> Patients { get; set; }
}

然后让您的 Controller 操作填充并将此 View 模型传递给 View :

public ActionResult Create()
{
    var model = new MyViewModel
    {
        Patients = db.Patients.ToList().Select(p => new SelectListItem
        {
            Value = p.Patient_ID.ToString(),
            Text = string.Format("{0}-{1}-{2}", p.Patient_ID, p.First_Name, p.Last_Name)
        });
    };
    return View(model);
} 

最后在强类型 View 中显示下拉列表:

@model MyViewModel
@using (Html.BeginForm())
{
    @Html.DropDownListFor(
        x => x.SelectedPatientId, 
        Model.Patients, 
        "-- Select patient ---"
    )
    @Html.ValidationMessageFor(x => x.SelectedPatientId)
    <button type="submit">OK</button>
}