Asp.net 如何在视图MVC4的详细操作中显示相关表中的数据？

我想使用ViewModel显示相关表中的详细信息视图

所以我创建了详细操作方法，但它不起作用

 public ActionResult Details(int id)
    {

        IQueryable<EntryViewModel> query = (from cat in _db.Categories
                 join en in _db.Entries on cat.Id equals en.CategoryId
                 where en.Id == id
                 select new EntryViewModel
                 {
                     Title = en.Title,
                     Username = en.Username,
                     Password = en.Password,
                     Url = en.Url,
                     Description = en.Description,
                     Category = cat.Name
                 }).AsQueryable();

        return View(query);
    }

视图：

---

有什么建议吗？

您必须在视图中设置模型，如：

@model IQueryable<PasswordCloudApp.ViewModels.EntryViewModel>

您的模型的类型为PasswordCloudApp.ViewModels.EntryViewModel，但您正在从控制器传递IQueryable

由于您希望单个项目具有一个id，因此可以更改控制器代码以返回该单个项目，如果未找到，则可能返回404：

public ActionResult Details(int id)
{

    EntryViewModel model = (from cat in _db.Categories
                            join en in _db.Entries on cat.Id equals en.CategoryId
                            where en.Id == id
                            select new EntryViewModel
                            {
                                Title = en.Title,
                                Username = en.Username,
                                Password = en.Password,
                                Url = en.Url,
                                Description = en.Description,
                                Category = cat.Name
                            }).FirstOrDefault();

    if (model == null) return HttpNotFound();

    return View(model);
}

实际上，您已将PasswordCloudApp.ViewModels.EntryViewModel与视图绑定，但您正在传递Iqueryable，因此在从操作返回视图时，您可以将结果的FirstOrDefault关联起来，或者更改视图中的@model Iqueryable

public ActionResult Details(int id)
    {

        IQueryable<EntryViewModel> query = (from cat in _db.Categories
                 join en in _db.Entries on cat.Id equals en.CategoryId
                 where en.Id == id
                 select new EntryViewModel
                 {
                     Title = en.Title,
                     Username = en.Username,
                     Password = en.Password,
                     Url = en.Url,
                     Description = en.Description,
                     Category = cat.Name
                 }).AsQueryable();

        return View(query.FirstOrDefault());
    }

---

请发布您的查看内容！我在找的地方。谢谢但现在我又犯了一个错误。”System.Linq.IQueryable'不包含'Title'的定义，并且找不到接受'System.Linq.IQueryable'类型的第一个参数的扩展方法'Title'。是否缺少using指令或程序集引用？。有什么问题吗？使用如下元素：@Html.TextBoxFormodel=>model.FirstOrDefault.Title

public ActionResult Details(int id)
{

    EntryViewModel model = (from cat in _db.Categories
                            join en in _db.Entries on cat.Id equals en.CategoryId
                            where en.Id == id
                            select new EntryViewModel
                            {
                                Title = en.Title,
                                Username = en.Username,
                                Password = en.Password,
                                Url = en.Url,
                                Description = en.Description,
                                Category = cat.Name
                            }).FirstOrDefault();

    if (model == null) return HttpNotFound();

    return View(model);
}

public ActionResult Details(int id)
    {

        IQueryable<EntryViewModel> query = (from cat in _db.Categories
                 join en in _db.Entries on cat.Id equals en.CategoryId
                 where en.Id == id
                 select new EntryViewModel
                 {
                     Title = en.Title,
                     Username = en.Username,
                     Password = en.Password,
                     Url = en.Url,
                     Description = en.Description,
                     Category = cat.Name
                 }).AsQueryable();

        return View(query.FirstOrDefault());
    }