Asp.net mvc 尝试插入带有外键的记录时无法使用LINQ保存？

我在网上找不到任何东西。我有一个

ReservationDate

型号

namespace Mijem_test_app.Models
{
    [HandleError]
 /*
     This model includes the location,
     the person who reserved it and
     FOR when they reserved it (not
     when they reserved it)
*/
    public class ReservationDate
    {
        //key
        public int Id { get; set; }

        //location name
        [Required]
        public Reservation Reservation { get; set; }

        //contact
        [Required]
        public Contact Contact { get; set; }

        //date reserved for
        [Required]
        public DateTime ReservedDate { get; set; }

        //information from textbox
        [Required]
        public string InfoFromTextBox { get; set; }

        public bool Deleted { get; set; }

        public ImagesUploaded ImageURL { get; set; }
    }
}

在我的控制器中，我尝试创建一条记录

[HttpPost]
public ActionResult Save(ReservationDate reservation)
{
    var _contactID = (int) TempData["ContactID"];

    var _contact = _context.Contacts
        .Single(r => r.Id == _contactID);

    var _location = _context.Reservations
        .Single(r => r.Name == reservation.Reservation.Name);

    var _ReservedDate = (DateTime)TempData["BookDate"];

    var _InfoFromTextBox = (string)TempData["InfoFromTextBox"];

    var __reservation = new ReservationDate
    {
        ReservedDate = _ReservedDate,
        Contact = _contact.Id,
        Reservation = _location.Id,
        InfoFromTextBox = _InfoFromTextBox,
        Deleted = false
    };

    _context.ReservationDates.Add(__reservation);

    _context.SaveChanges();

    return View("Index");
}

密码在某个时间断开

    Contact = _contact.Id,
    Reservation = _location.Id,

调试器告诉我，

无法将类型“int”隐式转换为“app.Models.Contact”

和

无法分别将类型“int”隐式转换为“app.Models.Reservation”

。我做错了什么？我的

预订

和

联系人

型号为

namespace app.Models
{
    [HandleError]
    public class Reservation
    {
        //unique ID of location
        public int Id { get; set; }

        //name of location
        [Required]
        [StringLength(255)]
        public string Name { get; set; }

        public int Ranking { get; set; }

        public bool Favorites { get; set; }

    }
}

以及

---

我什么都试过了。。我想也许我用错了LINQ？我在这里不知所措。

在课堂预订日期中，您需要具有联系人和预订表的导航属性。 添加联系人ID和保留ID这样的属性

public class ReservationDate
    {
        //key
        public int Id { get; set; }

        public int ReservationId { get; set; } // this
        //location name
        [Required]
        public Reservation Reservation { get; set; }

        public int ContactId { get; set; } // this
        //contact
        [Required]
        public Contact Contact { get; set; }

        //date reserved for
        [Required]
        public DateTime ReservedDate { get; set; }

        //information from textbox
        [Required]
        public string InfoFromTextBox { get; set; }

        public bool Deleted { get; set; }

        public ImagesUploaded ImageURL { get; set; }
    }

 ContactId = _contact.Id

MVC会自动将该联系人IDFK绑定到联系人表PKID

保存时，您可以调用联系人ID，而不是联系人这样的对象

public class ReservationDate
    {
        //key
        public int Id { get; set; }

        public int ReservationId { get; set; } // this
        //location name
        [Required]
        public Reservation Reservation { get; set; }

        public int ContactId { get; set; } // this
        //contact
        [Required]
        public Contact Contact { get; set; }

        //date reserved for
        [Required]
        public DateTime ReservedDate { get; set; }

        //information from textbox
        [Required]
        public string InfoFromTextBox { get; set; }

        public bool Deleted { get; set; }

        public ImagesUploaded ImageURL { get; set; }
    }

 ContactId = _contact.Id

---

您的

Reservation

属性的类型为

Reservation

，但您正在尝试为其分配

int

（通过使用

Reservation=\u location.Id，

）。这个错误可以通过使用

Reservation=\u location，

来解决，但是您的模型确实应该包含

int ReservationId

导航属性（与

Contact

相同）