//主键
[Key]
public Guid Id { get; set; }
//自增主键
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public Guid UserGuid { get; set; }
//可空字段
public Guid? TenantId { get; set; }
//非空字段
[Required]
public int RechargeDays { get; set; }
//固定类型
[Column(TypeName ="datetime")]
public System.DateTime RechargeTime { get; set; }
//固定类型与长度
[Column(TypeName ="nvarchar(200)")]
public string Remark { get; set; }
//最大 最小长度
[MaxLength(30), MinLength(5)]
public string CategoryName { get; set; }