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Entity Framework Code First级联删除

使用Data Annotations:

如果我们要到一对主从表增加级联删除,则要在主表中的引用属性上增加Required关键字,如:

 public class Destination
    {
        public int DestinationId { get; set; }
        public string Name { get; set; }
        public string Country { get; set; }
        public string Description { get; set; }
        public byte[] Photo { get; set; }
        public List<Lodging> Lodgings { get; set; }
    }

    public class Lodging
    {
        public int LodgingId { get; set; }
        public string Name { get; set; }
        public string Owner { get; set; }
        public bool IsResort { get; set; }
        public decimal MilesFromNearestAirport { get; set; }
        [Required]
        public Destination Destination { get; set; }
    } 

可以看到,在生成的数据库中,外键应用了级联删除规则

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使用Fluent API:

modelBuilder.Entity<Lodging>().HasRequired(l => l.Destination).WithMany(d => d.Lodgings).WillCascadeOnDelete(true);

 相对应的,如果要关闭级联功能则为:

modelBuilder.Entity<Lodging>().HasRequired(l => l.Destination).WithMany(d => d.Lodgings).WillCascadeOnDelete(false);

 

Entity Framework Code First级联删除