????? 大家可能會經常遇到接口需要經常增加新的方法和實現，可是我們原則上是不建議平凡的增加修改刪除接口方法，熟不知這樣使用接口是不是正確的接口用法，比如我見到很多的項目分層都是IDAL，DAL，IBLL，BLL，使用了2層接口，名義上是數據隔離和業務隔離，但是會使代碼難調試，難維護，有可能代碼寫的不好或者需求變更造成IBLL,BLL,IDAL,DAL的全部修改，這真的是代碼架構之瘍。

????? 基于上述觀點，我i重構DAL來廢除IDAL，IBLL造成的架構臃腫

使用模板模式創建Get和GetList方法，使他具有分頁和多表查詢，事務查詢的能力

使用命令模式創建AddWhere方法，使他具有Where族的能力，能處理復雜SQL查詢的能力

通過此模式，程序員可以在BLL中自由組合Where,Order,Gounp by不需要寫一個方法，再也不會在DAL中出現GetByName，GetListByType這樣的方法。

如需遷移redis和mongodb，建議重新搞一套redis的Base

代碼大致如下

AbsSelectBase.cs

public class AbsSelectBase<T> where T : BaseModel{private List<absWhere> lWhere { get; set; }public PageModel page { get; set; }protected string Table { get; set; }public RBase1(){page = new PageModel();lWhere = new List<absWhere>();Init();}protected virtual void Init(){}public virtual List<T> GetList(MySqlTransaction tran = null){string where;var lpar = GetWhere(out where);var list = new List<T>();if (page.Order_field.IsNull()){page.Order_field = "Id desc";}if (page.Current_Page.HasValue){list = GetPageList("", page.Order_field, Table, page, where, "", lpar, tran);}else{list = Query("select * from " + Table + " where " + where, page.Order_field, lpar, tran);}return list;}public void AddWhere(absWhere where){lWhere.Add(where);}public T Get(MySqlTransaction tran = null){page.Current_Page = 1;page.Page_Size = 1;var entity = GetList(tran).FirstOrDefault();return entity;}public virtual DynamicParameters GetWhere(out string where){DynamicParameters lpar = new DynamicParameters();where = " IsValid=1 ";foreach (var ewhere in lWhere){where += ewhere.CreateWhere(lpar);}lWhere.clear();lWhere=null;return lpar;}public object GetCount(MySqlTransaction tran = null){string where = "";var lpar = GetWhere(out where);var res = SqlConnections.Sqlconnection.Query<int>("select count(1) from " + Table + " where " + where, lpar, tran);return res;}protected virtual List<T> GetPageList(string Field, string Order, string Table, PageModel model, string Where, string bigOrderBy = null, object param = null,MySqlTransaction sqlTransation = null){var res = SqlConnections.Sqlconnection.GetPageList<T>(Field, Order, Table, model, Where, bigOrderBy, param, sqlTransation).ToList();return res;}}

ConcreteSelectA.cs

public class RScoreRecordSelect : RBase1<ScoreRecord>{public RScoreRecordSelect(){ }}

ConcreteSelectB.cs，多表

/// <summary>/// ProductBuy inner join User/// </summary>public class RProBuyUserSelect : RBase1<ProductBuy>{public override List<ProductBuy> GetList(MySql.Data.MySqlClient.MySqlTransaction tran = null){string where;var lpar = GetWhere(out where);var list = new List<ProductBuy>();string table = @" User inner join ProductBuy on User.ID=ProductBuy.UserID ";if (page.Order_field.IsNull()){page.Order_field = "ProductBuy.Id desc";}if (page.Current_Page.HasValue){list = GetPageList("", page.Order_field, table, page, where, "", lpar, tran);}else{list = Query("select ProductBuy.* from " + table + " where " + where, page.Order_field, lpar, tran);}return list;}public override CZCore.Data.DynamicParameters GetWhere(out string where){DynamicParameters lpar = new DynamicParameters();where = " User.IsValid=1 and ProductBuy.IsValid=1 ";foreach (var ewhere in lWhere){where += ewhere.CreateWhere(lpar);}return lpar;}public enum EnumOrder{/// <summary>/// /// </summary>[Category("UserAct.BuyCount")][Description("")]_0,/// <summary>/// /// </summary>[Category("UserAct.BuyMoney")][Description("")]_1,/// <summary>/// /// </summary>[Category("UserAct.CashScore")][Description("")]_2,/// <summary>/// /// </summary>[Category("DBB.Money")][Description("")]_3,/// <summary>/// /// </summary>[Category("DBB.Score")][Description("")]_4}}

absWhere.cs

public abstract class absWhere{private string _field;public string field{get{return _field;}set{_field = value;}}public object value { get; set; }private string _par;public string par{get{if (_par.IsNull()){_par = field.Replace(".","");}return _par;}set{_par = value;}}public abstract string CreateWhere(DynamicParameters lpar);}

WhereAndIn.cs

public class WhereAndIn : absWhere{public override string CreateWhere(CZCore.Data.DynamicParameters lpar){string sql="";if (value.IsNull() == false){sql = " and "+field+" in @"+par+" ";lpar.Add(par, value);}return sql;}}

WhereAndLike.cs

public class WhereAndLike : absWhere{public override string CreateWhere(CZCore.Data.DynamicParameters lpar){string sql="";if (value.IsNull() == false){sql = " and "+field+" like @"+par+" ";lpar.Add(par, "%"+value+"%");}return sql;}}

單表查詢

多表查詢

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簡單的處理增刪改查主鍵，等于Entity屬性的簡單查詢不分頁功能，并在上層提供一個總的facade門面

AbsBase.cs

public class RBase<T> where T : BaseModel{public List<T> GetAll(MySqlTransaction tran = null){var list = SqlConnections.Sqlconnection.GetAll<T>(tran);return list;}public T GetById(object id, MySqlTransaction tran = null){var res = SqlConnections.Sqlconnection.GetById<T>(id, tran);return res;}public UInt64 Insert(T T, MySqlTransaction tran = null, MySqlConnection _conn = null, bool IsAuto = true){var res = SqlConnections.Sqlconnection.Insert<T>(T, tran, IsAuto);return res;}public void Insert(List<T> list, MySqlTransaction tran = null, MySqlConnection _conn = null){SqlConnections.Sqlconnection.Insert<T>(list, tran);}public void Update(T T, MySqlTransaction tran = null, MySqlConnection _conn = null){SqlConnections.Sqlconnection.Update<T>(T, tran);}public void Update(List<T> list, MySqlTransaction tran = null, MySqlConnection _conn = null){SqlConnections.Sqlconnection.Update<T>(list, tran);}public List<T> Search(T t, MySqlTransaction tran = null, MySqlConnection _conn = null){var res = SqlConnections.Sqlconnection.Search<T>(t, tran);return res;}public bool Delete(object id, bool isDelete = false, MySqlTransaction tran = null, MySqlConnection _conn = null){var res = SqlConnections.Sqlconnection.Delete<T>(id, tran, isDelete: isDelete);return res;}public void DeleteBySearch(T t, bool isDelete = false, MySqlTransaction tran = null, MySqlConnection _conn = null){SqlConnections.Sqlconnection.DeleteBySearch<T>(t, tran, isDelete: isDelete);}public RBase(){Init();}public virtual void Init(){}public void TruncateTable(MySqlTransaction sqlTransation = null){bool result = Execute(string.Format("Truncate Table {0}","`" + typeof(T).Name.ToLower() + "`"), null, sqlTransation) > 0;}}

Concrete1.cs

public class RScoreRecord:RBase<ScoreRecord>{}

Facade.cs

Model層封裝Entity層,并懶加載Entity數據，只加載關聯id一級數據

MUser.cs

public class MUser{private User eUser;public MUser(User _eUser){eUser=_eUser;}private UserAct eUserAct;public UserAct GetEUserAct(MySql.Data.MySqlClient.MySqlTransaction ts = null){if (eUserAct == null){eUserAct = RCommon.rUserAct.GetById(eUser.Id,ts);}return eUserAct;}private DBB eDBB;public DBB GetDBB(MySql.Data.MySqlClient.MySqlTransaction ts=null){if (eDBB == null){eDBB = RCommon.rdbb.GetById(eUser.Id,ts);}return eDBB;}}

轉載于:https://www.cnblogs.com/alisande/p/5587063.html

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