MVVMCross社区SqLite – 表之间的关系

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

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.

（编辑：李大同）

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