EF Core 5-在自定义连接表中设置自定义属性值

// 连接表实体类
public class CustomEntity
{
    public int Entity1Id { get; set; }
    public Entity1 Entity1 { get; set; }

    public int Entity2Id { get; set; }
    public Entity2 Entity2 { get; set; }

    public string CustomProperty { get; set; }
}

// 实体类1
public class Entity1
{
    public int Id { get; set; }
    public string Name { get; set; }

    public ICollection<CustomEntity> CustomEntities { get; set; }
}

// 实体类2
public class Entity2
{
    public int Id { get; set; }
    public string Name { get; set; }

    public ICollection<CustomEntity> CustomEntities { get; set; }
}

// DbContext类中的配置
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<CustomEntity>()
        .HasKey(c => new { c.Entity1Id, c.Entity2Id });

    modelBuilder.Entity<CustomEntity>()
        .HasOne(c => c.Entity1)
        .WithMany(e => e.CustomEntities)
        .HasForeignKey(c => c.Entity1Id);

    modelBuilder.Entity<CustomEntity>()
        .HasOne(c => c.Entity2)
        .WithMany(e => e.CustomEntities)
        .HasForeignKey(c => c.Entity2Id);

    modelBuilder.Entity<CustomEntity>()
        .Property(c => c.CustomProperty)
        .HasMaxLength(100);
}

// 添加数据
var entity1 = new Entity1 { Name = "Entity 1" };
var entity2 = new Entity2 { Name = "Entity 2" };
var customEntity = new CustomEntity
{
    Entity1 = entity1,
    Entity2 = entity2,
    CustomProperty = "Custom Value"
};

dbContext.Add(customEntity);
dbContext.SaveChanges();