public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
        {
            var db = new 客戶資料Entities();
            var data = db.客戶資料.Find(this.客戶Id);

            foreach (var item in data.客戶聯絡人)
            {
                if (item.Email.Equals(this.Email) && (bool)!this.是否已刪除)
                {
                    yield return new ValidationResult("電子郵件重複", new[] { "Email" });
                }
            }
        }
 public EFUnitOfWork()
 {
     Context = new 客戶資料Entities();
 }