Question

我有一个表单使用POST方法将数据发送到我的控制器上的Create操作（注释为[HttpPost]）。动作签名需要Visit。问题是只有Visit上的一些属性被填充，尽管视图中的所有属性都填充在屏幕上。仅填充将数据输入到文本框中的属性。下拉列表中没有任何值传递给模型。

有什么想法在这里发生了什么？谢谢！

MVC 4 Beta。

更新1-视图中使用的表单...

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

    <fieldset>
        <legend>Visit</legend>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.VisitDate)
            </div>
            <div class="editor-field">
                @Html.TextBoxFor(model => model.Visit.VisitDate, new { @class = "editor-field-medium" })
                @Html.ValidationMessageFor(model => model.Visit.VisitDate)
            </div>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.NPN)
            </div>
            <div class="editor-field">
                @Html.TextBoxFor(model => model.Visit.NPN, new { @class = "editor-field-medium" })
                @Html.ValidationMessageFor(model => model.Visit.NPN)
            </div>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.AppointmentTypeId)
            </div>
            <div class="editor-field"> @* THIS DOES NOT GET POPULATED WHEN PASSED TO THE ACTION*@
                @Html.DropDownList("AppointmentTypeId", String.Empty)
                @Html.ValidationMessageFor(model => model.Visit.AppointmentTypeId)
            </div>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.EducationId)
            </div>
            <div class="editor-field"> @* THIS DOES NOT GET POPULATED WHEN PASSED TO THE ACTION*@
                @Html.DropDownList("EducationId", String.Empty)
                @Html.ValidationMessageFor(model => model.Visit.EducationId)
            </div>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.PsychologistId)
            </div>
            <div class="editor-field"> @* THIS DOES NOT GET POPULATED WHEN PASSED TO THE ACTION*@
                @Html.DropDownList("PsychologistId", String.Empty)
                @Html.ValidationMessageFor(model => model.Visit.PsychologistId)
            </div>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.PsychometristId)
            </div>
            <div class="editor-field"> @* THIS DOES NOT GET POPULATED WHEN PASSED TO THE ACTION*@
                @Html.DropDownList("PsychometristId", String.Empty)
                @Html.ValidationMessageFor(model => model.Visit.PsychometristId)
            </div>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.PostDoctoralId)
            </div>
            <div class="editor-field"> @* THIS DOES NOT GET POPULATED WHEN PASSED TO THE ACTION*@
                @Html.DropDownList("PostDoctoralId", String.Empty)
                @Html.ValidationMessageFor(model => model.Visit.PostDoctoralId)
            </div>
            <div class="editor-label">
                @Html.LabelFor(model => model.Visit.BehavioralObservations)
            </div>
            <div class="editor-field">
                @Html.EditorFor(model => model.Visit.BehavioralObservations)
                @Html.ValidationMessageFor(model => model.Visit.BehavioralObservations)
            </div>
        <p>
            <input type="submit" value="Create Visit" />
        </p>
    </fieldset>
}

Answer 1

您的模型状态可能无效。这是一个扩展方法，它将模型状态和转储错误读取到调试日志中：

public static class ModelExtensions
{
    public static void DumpErrors(this System.Web.Mvc.ModelStateDictionary ModelState)
    {
        var errors = from key in ModelState
                     let errorList = ModelState[key.Key].Errors
                     where errorList.Any()
                     select new
                     {
                         Item = key.Key,
                         Value = key.Value,
                         errorList
                     };

        foreach (var errorList in errors)
        {
            System.Diagnostics.Debug.WriteLine("MODEL ERROR:");
            System.Diagnostics.Debug.WriteLine(errorList.Item);
            System.Diagnostics.Debug.WriteLine(errorList.Value);
            foreach (var error in errorList.errorList)
            {
                System.Diagnostics.Debug.WriteLine(error.ErrorMessage);
                System.Diagnostics.Debug.WriteLine(error.Exception);
            }
            System.Diagnostics.Debug.WriteLine("-----");
        }
    }
}

在有问题的行动的第一行调用它，设置一个断点，并查看它的内容。

ModelState.DumpErrors();

Answer 2

您的下拉列表中没有任何内容。你有：

@Html.DropDownList("AppointmentTypeId", String.Empty)

所以你没有选择的选项。 AppointmentTypeId的属性Visit将始终为空。您的选择列表应填充具有相关文本和值的选项：

查看

@{ List<Appointment> appointmentTypes = ViewBag.AppointmentTypeOptions; var appointmentList = new SelectList(list, "AppointmentID", "Description"); } @Html.DropDownListFor(x => x.AppointmentTypeId, appointmentList)

<强>控制器

ViewBag.AppointmentTypeOptions = someDataStore.getAppointmentTypes();

注意我已使用ViewBag使这更简单，并允许在HTTP帖子中继续使用您的Visit类。如果您愿意，可以创建一个ViewModel来保存这些列表的信息。

Answer 3

使用一个属性映射到一个属性以及一个包含可用选项的属性...例如PsychometristId和心理医生列表。然后使用DropDownListFor而不是DropDownList。试试这样的事情

 @Html.DropDownListFor("PsychometristId", new SelectList(Psychometrists, "name", "id"))

为什么我的模型没有填充下拉列表中的属性？

3 个答案: