Question

我一直在讨论如何处理这种情况。我有一个模型，项目模型，它有许多项目需要下拉，以便用户更改所选的项目。我从ProjectType值开始简单，它应该具有从ProjectTypes表填充的可选值。这是ViewModel：

    public class ProjectViewModel
{

    public APT_Projects Project { get; set; }
    public System.Linq.IQueryable<APT_ProjectTypes> projecttypes { get; set; }
    public APT_ClientTypes ClientTypes {get; set;}

}

这是控制器：

        public ActionResult Edit(int id = 0)
    {



        APT_Projects apt_projects = db.APT_Projects.Find(id);
        if (apt_projects == null)
        {
            return HttpNotFound();
        }

        ProjectViewModel Project = new ProjectViewModel();

        var apt_projecttypes = from a in db.APT_ProjectTypes
                                            select a;


        Project.Project = apt_projects;
        Project.projecttypes = apt_projecttypes;

        return View(Project);
    }

最后是观点：

@model APTII_MVC.ViewModel.ProjectViewModel 

@{
    ViewBag.Title = "Edit";
}

<h2>Edit</h2>

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


<fieldset>
    <legend>APT_Projects</legend>

    <div class="editor-label" style="float: left; width: 500px;"  >
        @Html.LabelFor(model => model.Project.Project_ID)
    </div>
    <div class="editor-field" style="float: left; width: 500px;" >
        @Html.EditorFor(model => model.Project.Project_ID)
        @Html.ValidationMessageFor(model => model.Project.Project_ID)
    </div>

    <div class="editor-label"">
        @Html.LabelFor(model => model.Project.ProjectType_ID)
    </div>
    <div class="editor-field"">
        @Html.DropDownListFor(model => model.Project.ProjectType_ID, Model.projecttypes)
    </div>

    <p>
        <input type="submit" value="Save" />
    </p>
</fieldset>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

当我以这种方式执行此操作时，.net不喜欢Drowpdownlistfor，但我不清楚如何以dropdownlistfor接受的方式使用这些值。我的错是什么？

编辑：下拉列表的相关错误。

'System.Web.Mvc.HtmlHelper<ViewModel.ProjectViewModel>' does not contain a definition for 'DropDownListFor' and the best extension method overload 'System.Web.Mvc.Html.SelectExtensions.DropDownListFor<TModel,TProperty>(System.Web.Mvc.HtmlHelper<TModel>, System.Linq.Expressions.Expression<System.Func<TModel,TProperty>>, System.Collections.Generic.IEnumerable<System.Web.Mvc.SelectListItem>)' has some invalid arguments c:\Visual Studio 2012\Projects\Test_MVC\Test_MVC\Views\Project\Edit.cshtml

Answer 1

您可能需要List<SelectListItem>或SelectList() ..因此请尝试将projecttypes对象转换为

@Html.DropDownListFor(model => model.Project.ProjectType_ID, new SelectList(Model.projecttypes,"ID","Type")

或将您的viewmodel编辑为

public SelectList projecttypes { get; set; }

和您的控制器代码

Project.projecttypes = new SelectList(db.APT_ProjectTypes,"ID","Type");

只是猜测你的价值/文字字段名称

使用一个模型填充另一个模型上的视图的下拉列表

1 个答案: