我有两个简单的表格如下：
public class MediaPartner
{
[PrimaryKey,AutoIncrement]
public int Id { get; set; }
public string PhoneNumber { get; set; }
public string CompanyName { get; set; }
public double Lat { get; set; }
public double Lng { get; set; }
public DateTime InsertedUtc { get; set; }
}
public class ImageGroup
{
[PrimaryKey,AutoIncrement]
public int Id { get; set; }
public List<MediaPartner> IdMediaPartner { get; set; }
public string ImagePath { get; set; }
public bool IsSent { get; set; }
public DateTime InsertedUtc { get; set; }
}
问题：
public List< MediaPartner > IdMediaPartner { get; set; }
OR
public MediaPartner IdMediaPartner { get; set; }
does not compile.
我的问题是：有没有办法在这两个表之间建立一对多的关系？
谢谢！
解决方法
sqlite-net仅使用索引提供跨表引用,如：
public class Stock
{
[PrimaryKey,AutoIncrement]
public int Id { get; set; }
[MaxLength(8)]
public string Symbol { get; set; }
}
public class Valuation
{
[PrimaryKey,AutoIncrement]
public int Id { get; set; }
[Indexed]
public int StockId { get; set; }
public DateTime Time { get; set; }
public decimal Price { get; set; }
}
sqlite-net至少有一个扩展,它允许声明OneToMany属性 – 参见https://bitbucket.org/twincoders/sqlite-net-extensions,它可以启用以下代码：
public class Stock
{
[PrimaryKey,AutoIncrement]
public int Id { get; set; }
[MaxLength(8)]
public string Symbol { get; set; }
[OneToMany] // One to many relationship with Valuation
public List<Valuation> Valuations { get; set; }
}
public class Valuation
{
[PrimaryKey,AutoIncrement]
public int Id { get; set; }
[ForeignKey(typeof(Stock))] // Specify the foreign key
public int StockId { get; set; }
public DateTime Time { get; set; }
public decimal Price { get; set; }
[ManyToOne] // Many to one relationship with Stock
public Stock Stock { get; set; }
}
我不确定这个的确切实现 – 例如我不知道这是否使用真正的FOREIGN KEY约束 – 但代码是开源的,正在积极开发中,内置mvvmcross插件支持,是跨平台的,可用于分叉和贡献.
