具有sqlite本地存儲的Windows Phone應用

Question

我正在嘗試使用SQLite將從JSON對象保存到local storage數據庫中

我已經導入了很多軟件包以及SQLite框架。

我也做了這兩節課： 活動

public class Activity : INotifyPropertyChanged
    {
        [SQLite.PrimaryKey, SQLite.AutoIncrement]
        public int act_id
        {
            get;
            set;
        }
        //The Id property is marked as the Primary Key
        private int act_organization_id_value;
        private int act_creator_id_value;
        private int act_free_value;
        private int act_subcription_value;
        private int act_external_value;
        private int act_active_value;
        private int act_future_value;
        private int act_status_value;
        private int act_viewed_value;
        private string act_location_value = String.Empty;
        private string act_lng_value = String.Empty;
        private string act_title_value = String.Empty;
        private string act_information_value = String.Empty;
        private string act_type_value = String.Empty;
        private string act_color_value = String.Empty;
        private string act_event_identifier_value = String.Empty;
        private DateTime act_start_value = DateTime.Now;
        private DateTime act_end_value = DateTime.Now;

         [OneToMany(CascadeOperations = CascadeOperation.All)]
        public List<ActivityMember> membrs { get; set; }

       //Other getters and setters
}

活動成員

   public class ActivityMember : INotifyPropertyChanged
    {
        [SQLite.PrimaryKey, SQLite.AutoIncrement]
        public int mem_id
        {
            get;
            set;
        }

        private int mem_activity_id_value;
        private int mem_organization_id_value;
        private int mem_role_id_value;
        private int mem_creator_value;
        private int mem_accepted_value;
        private int mem_activity_accepted_value;
        private int mem_active_value;
        private int mem_deleted_value;
        private string mem_profile_color_value = String.Empty;
        private string mem_picture_value = String.Empty;
        private string mem_email_value = String.Empty;
        private string mem_phone_value = String.Empty;
        private string mem_gsm_value = String.Empty;
        private string mem_address_value = String.Empty;
        private string mem_postal_value = String.Empty;
        private string mem_city_value = String.Empty;
        private string mem_country_id_value = String.Empty;
        private string mem_first_name_value = String.Empty;
        private string mem_last_name_value = String.Empty;
        private string mem_extra_info_value = String.Empty;
        private string mem_street_value = String.Empty;
        private string mem_streetnumber_value = String.Empty;
        private string mem_gender_value = String.Empty;
        private DateTime mem_birthdate_value = DateTime.Now;

        [ManyToOne]      // Many to one relationship with Activity
        public Activity activity { get; set; }

        // all other getters and setters
}

一個活動可以有更多的ActivityMembers。 構建並運行時，出現以下錯誤：

在調試時，我發現它是由以下幾行引起的：在活動中：

   [OneToMany(CascadeOperations = CascadeOperation.All)]
        public List<ActivityMember> membrs { get; set; }

活動中的成員：

  [ManyToOne]      // Many to one relationship with Activity
    public Activity activity { get; set; }

任何有關如何正確執行此操作的幫助？

編輯我有這些參考：

Answer 1

該錯誤是由SQLite.Net嘗試使用List<ActivityMember>類型序列化屬性引起的，該屬性是SQLite.Net不知道的類型。 通過使用SQLite-Net擴展OneToMany屬性進行注釋，SQLite.Net應該忽略它，因為OneToMany繼承自SQLite.Net Ignore屬性。

如果該屬性未被SQLite.Net忽略，則是因為無法識別“ Ignore屬性。 通常是由於您使用的SQLite.Net版本與針對SQLite-Net Extensions的版本不同而引起的。 要解決此問題，必須確保使用的SQLite.Net版本相同。

為了解決這個問題，您可以將SQLite-Net擴展源復制到項目中，以強制庫鏈接到您的SQLite-Net版本。

回應編輯 ：

如您在參考文獻中所見，您有兩個SQLite.Net庫：

• SQLite.Net（及其異步API SQLite.Net.Async）
• Windows Phone的SQLite

您必須刪除對SQLiteNetExtensions ， SQLite.Net.Async和SQLite.Net.Async的引用，並SQLite For Windows Phone的SQLite For Windows Phone庫編譯SQLite-Net Extensions源 。