DatabaseGeneratedOption [DatabaseGenerated(DatabaseGeneratedOption.Identity)] 添加时 获取值 自增 默认值,,后期无法修改如:Id(AUTO_INCREMENT,自增) , AddDatetime (CURRENT_TIMESTAMP|getdate()) [DatabaseGenerated(DatabaseGeneratedOption.Computed)] 更新时 获取值 修改即自动生成值 如firstname lastname-->fullname , UpdateDatetime(CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP) [DatabaseGenerated(DatabaseGeneratedOption.None)] 没有生成值