一对多流利的实体框架

Question

每隔半小时，将收到来自移动设备的请求。可以在设备表中验证移动设备，然后将记录添加到Ping表中。使用实体Franmework将相同的表映射到DB。谁能告诉我如何将Device.Id（主键）映射到Ping.IdDevice（外键），则使用Fluent Api可以实现一对多的关系。public class Ping {    public long Id { get; set; }    public long IdDevice { get; set; }    public string Request { get; set; }    public string Response { get; set; }    public int RspCode { get; set; }    public DateTime CreatedDateTime { get; set; }}    public class Device {    public long Id { get; set; }    public string Uid { get; set; }    public Type Type { get; set; }    public Status Status { get; set; }}        protected override void OnModelCreating(DbModelBuilder modelBuilder) {        modelBuilder.Entity<Device>().HasKey(d => d.Id);        modelBuilder.Entity<Device>().Property(d => d.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);        modelBuilder.Entity<Device>().Property(d => d.Uid).HasMaxLength(8);        modelBuilder.Entity<Device>().HasRequired(d => d.Uid);        modelBuilder.Entity<Ping>().HasKey(p => p.Id);        modelBuilder.Entity<Ping>().Property(p => p.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);        base.OnModelCreating(modelBuilder);    }

Answer 1

您可以尝试在Ping类中为Device添加导航属性，如下所示：

public class Ping

{

    public long Id { get; set; }

    public long IdDevice { get; set; }

    public virtual Device Device { get; set; }//Newly added

    public string Request { get; set; }

    public string Response { get; set; }

    public int RspCode { get; set; }

    public DateTime CreatedDateTime { get; set; }

}

然后在Device类中为Ping添加导航属性，如下所示

public class Device

{

    public long Id { get; set; }

    public string Uid { get; set; }

    public Type Type { get; set; }

    public Status Status { get; set; }

    public virtual List<Ping> Pings { get; set; } //Newly added

}

最后，在OnModelCreating中添加以下映射：

modelBuilder.Entity<Device>().HasMany(d => d.Pings).WithRequired(p => p.Device).HasForeignKey(p => p.IdDevice);