/// <summary>
    /// 系统sku信息
    /// </summary>
    public class SkuInfo : BaseModel
    {
        /// <summary>
        /// SKU编码
        /// </summary>
        public string Code { get; set; }

        /// <summary> 关键字 </summary>
        public string Keyword { get; set; }

        /// <summary> 所属SPUID </summary>
        public long SpuId { get; set; }

        /// <summary> 所属SPU </summary>
        public virtual SpuInfo Spu { get; set; }

        /// <summary>对应规格ID</summary>
        public long SpuSpecificationId { get; set; }
        /// <summary>对应的规格</summary>
        public virtual SpuSpecification SpuSpecification { get; set; }

        /// <summary>对应颜色ID</summary>
        public long SpuColorId { get; set; }
        /// <summary>对应的颜色id</summary>
        public virtual SpuColor SpuColor { get; set; }

        /// <summary>对应的分销sku</summary>
        public virtual List<DistributorSku> DistributorSkus { get; set; }
    }
    public class SkuInfoConfig : IEntityTypeConfiguration<SkuInfo>
    {
        public void Configure(EntityTypeBuilder<SkuInfo> builder)
        {
            builder.HasKey(a => a.Id);
            builder.Property(m => m.Id)
                .ValueGeneratedOnAdd();
            builder.Property(m => m.ConcurrencyToken)
                .IsConcurrencyToken();

            builder.HasOne(a => a.SpuColor)
                .WithMany(a => a.Skus)
                .HasForeignKey(a => a.SpuColorId);
            builder.HasOne(a => a.SpuSpecification)
                .WithMany(a => a.Skus)
                .HasForeignKey(a => a.SpuSpecificationId);
            builder.HasOne(a => a.Spu)
                .WithMany(a => a.Skus)
                .HasForeignKey(a => a.SpuId);

            builder.Property(a => a.Code).HasMaxLength(128);
            builder.Property(a => a.Keyword).HasMaxLength(128);
        }
    }

        protected override void OnModelCreating(ModelBuilder builder)
        {
            base.OnModelCreating(builder);
            var mi = builder.GetType().GetMethod("ApplyConfiguration");
            var asm = Assembly.GetAssembly(this.GetType());
            asm.GetTypes()
                .Where(a => a.GetInterfaces().Any(i => i.FullName.Contains("Microsoft.EntityFrameworkCore.IEntityTypeConfiguration")))
                .Select(a =>
                {
                    return new { t = a.GetInterfaces().First().GenericTypeArguments.First(), o = asm.CreateInstance(a.FullName) };
                })
                .ToList().ForEach(a =>
                {
                    mi.MakeGenericMethod(a.t).Invoke(builder, new[] { a.o });
                });
        }