代码优先使用数据注释的多对多关系的一种方式

Question

我的应用程序中有两个模型：Stock 和 Report。一个报表可以有很多个股票，一个股票可以在多个报表中使用。

public enum ElectionType 
{
    MANAGER =1 , 
    INSPECTOR , 
    BOTH
}
public class Report
{
    public Report()
    {
        Stocks = new List<Stock>();
    }

    public int ReportID { get; set; }

    [Required]
    public DateTime ShamsiDate { get; set; }

    public int? StockID { get; set; }

    [Required]
    public  ElectionType  ElectionType { get; set; }

    [ForeignKey("StockID")]
    public virtual ICollection<Stock> Stocks { get; set;}
}
public class Stock
{
    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int StockID { get; set; }
    public int FinancialCode { get; set; }
    public String NationalCode { get; set; }
    public String FirstName { get; set; }
    public String LastName { get; set; }
    public String FatherName { get; set; }
    public String Place { get; set; }

    public int StockCount { get; set; }

    public int StockPrice { get; set; }
    public int StockSize { get; set; }

    public int StartStock { get; set; }

    public int EndStock { get; set; }

}

我想创建一种单向关系，因此无法从 Stock 访问 Report。我已经写了这段代码，但它不起作用。

Answer 1

要使用注释来完成，您需要一个连接点 table:

public class ReportStock
{
    [Key, Column(Order = 1)]
    public int ReportID { get; set; }
    [Key, Column(Order = 2)]
    public int StockID { get; set; }

    [ForeignKey("ReportID")]
    public virtual Report Report { get; set;}

    [ForeignKey("StockID")]
    public virtual Stock Stock { get; set;}
}

然后更改您的报告class：

public class Report
{
    public Report()
    {
        ReportStocks = new List<ReportStock>();
    }

    public int ReportID { get; set; }

    [Required]
    public DateTime ShamsiDate { get; set; }

    [Required]
    public  ElectionType  ElectionType { get; set; }

    public virtual ICollection<ReportStock> ReportStocks { get; set;}
}

代码优先使用数据注释的多对多关系的一种方式

Code first One way many to many relationship using data annotation

entity-framework

ef-code-first

代码优先 使用数据注释的多对多关系的一种方式

Code first One way many to many relationship using data annotation

entity-framework

ef-code-first

代码优先使用数据注释的多对多关系的一种方式