Question

我正在尝试将JSON对象保存到SQL Server数据库。因此，我在数据库中创建了两个表，“约会”和“邀请者”。

我生成的Json数据以及我使用jQuery $ .ajax（）发送的数据是

    {"Title":"Test",
        "Description":"fffffff",
        "Duration":"15 minuten",
        "Invitee":[
                    {
                      "Email":"e@g.com",
                      "Presence":"nodig"
                    },
                    {
                      "Email":"h@g.com",
                      "Presence":"gewenst"
                    },
                    {
                      "Email":"j@z.com",
                      "Presence":"info"
                    }
                  ]
  }

这两个表是

CREATE TABLE [dbo].[Appointments] (
[Id]          INT            IDENTITY (1, 1) NOT NULL,
[UserId]      INT            NOT NULL,
[Title]       NVARCHAR (100) NOT NULL,
[Description] NTEXT          NULL,
[Duration]    NVARCHAR (20)  NOT NULL,
PRIMARY KEY CLUSTERED ([Id] ASC)
);

和

CREATE TABLE [dbo].[Invitees] (
[Id]       INT            NOT NULL,
[AppId]    INT            NOT NULL,
[Email]    NVARCHAR (100) NOT NULL,
[Presence] NVARCHAR (15)  NOT NULL,
PRIMARY KEY CLUSTERED ([Id] ASC)
);

此外，我创建了这些模型，类和接口

    public class Appointment : IAppointments
{
    #region Implementation of IAppointments

    public int Id { get; set; }
    public int UserId { get; set; }
    public string Title { get; set; }
    public string Description { get; set; }
    public string Duration { get; set; }
    public List<Invitee> Invitee { get; set; }

    #endregion
};

interface IAppointments
{
    int Id { get; set; }
    int UserId { get; set; }
    string Title { get; set; }
    string Description { get; set; }
    string Duration { get; set; }
    List<Invitee> Invitee { get; set; }
};

和

    public class Invitee : IInvitee
{
    public int Id { get; set; }
    public int AppId { get; set; }
    public string Email { get; set; }
    public string Presence { get; set; }
};

interface IInvitee
{
    int Id { get; set; }
    int AppId { get; set; }
    string Email { get; set; }
    string Presence { get; set; }
};

在控制器中我有以下代码

        [HttpPost]
    public JsonResult NewAppSave(Appointment model)
    {
        if (ModelState.IsValid)
        {
            using (var db = new MainDbContext())
            {
                var appointment = db.Appointments.Create();
                var invitee = db.Invitees.Create();
                appointment.UserId = 1;
                appointment.Title = model.Title;
                appointment.Description = model.Description;
                appointment.Duration = model.Duration;
                db.Appointments.Add(appointment);
                foreach (var inv in model.Invitee)
                {
                    var newInv = new Invitee();
                    invitee.Email = newInv.Email;
                    invitee.Presence = newInv.Presence;
                };
                db.Invitees.Add(invitee);
                db.SaveChanges();
            }
        }
        else
        {
            ModelState.AddModelError("", "Something went wrong");
        }
        return Json(model);
    };

在foreach循环中的'model.Invitee'处生成NullReferenceException。

我无法弄清问题是什么。请帮帮....

使用两个数据库表中的被邀请者列表保存约会

0 个答案: