24、ASP.NET MVC入門到精通——數據庫倉儲

本系列目錄：ASP.NET MVC4入門到精通系列目錄匯總

業務層調用數據層對象，我不想每次都new一個數據層對象，而是在數據層創建一個倉儲，統一管理所有的對象調用。

1、在IDAL項目中，新建IDBSession.tt模板

<#@ template language="C#" debug="false" hostspecific="true"#>
<#@ include file="EF.Utility.CS.ttinclude"#><#@ output extension=".cs"#> 
<#
CodeGenerationTools code = new CodeGenerationTools(this);
MetadataLoader loader = new MetadataLoader(this);
CodeRegion region = new CodeRegion(this, 1);
MetadataTools ef = new MetadataTools(this);
string inputFile = @"..\MODEL\OA.edmx";
EdmItemCollection ItemCollection = loader.CreateEdmItemCollection(inputFile);
string namespaceName = code.VsNamespaceSuggestion();
EntityFrameworkTemplateFileManager fileManager = EntityFrameworkTemplateFileManager.Create(this);
#>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace IDAL
{
public partial interface IDBSession
{
<#
    // Emit Entity Types
foreach (EntityType entity in ItemCollection.GetItems<EntityType>().OrderBy(e => e.Name))
{
#>
   I<#=entity.Name#>DAL I<#=entity.Name#>DAL{get;set;}
<#}#>
}
}

Ctrl+S后自動生成IDBSession接口

 
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace IDAL
{
public partial interface IDBSession
{
   IBill_LeaveDAL IBill_LeaveDAL{get;set;}
   IoldWF_AutoTransactNodeDAL IoldWF_AutoTransactNodeDAL{get;set;}
   IoldWF_BillFlowNodeDAL IoldWF_BillFlowNodeDAL{get;set;}
   IoldWF_BillFlowNodeRemarkDAL IoldWF_BillFlowNodeRemarkDAL{get;set;}
   IoldWF_BillStateDAL IoldWF_BillStateDAL{get;set;}
   IoldWF_NodeDAL IoldWF_NodeDAL{get;set;}
   IoldWF_NodeStateDAL IoldWF_NodeStateDAL{get;set;}
   IoldWF_WorkFlowDAL IoldWF_WorkFlowDAL{get;set;}
   IoldWF_WorkFlowNodeDAL IoldWF_WorkFlowNodeDAL{get;set;}
   IOu_DepartmentDAL IOu_DepartmentDAL{get;set;}
   IOu_PermissionDAL IOu_PermissionDAL{get;set;}
   IOu_RoleDAL IOu_RoleDAL{get;set;}
   IOu_RolePermissionDAL IOu_RolePermissionDAL{get;set;}
   IOu_UserInfoDAL IOu_UserInfoDAL{get;set;}
   IOu_UserRoleDAL IOu_UserRoleDAL{get;set;}
   IOu_UserVipPermissionDAL IOu_UserVipPermissionDAL{get;set;}
   IW_WorkFlowDAL IW_WorkFlowDAL{get;set;}
   IW_WorkFlowBranchDAL IW_WorkFlowBranchDAL{get;set;}
   IW_WorkFlowNodeDAL IW_WorkFlowNodeDAL{get;set;}
   IW_WrokFlowRoleDAL IW_WrokFlowRoleDAL{get;set;}
   IWR_WorkFlowApplyDAL IWR_WorkFlowApplyDAL{get;set;}
   IWR_WrokFlowApplyDetailsDAL IWR_WrokFlowApplyDetailsDAL{get;set;}
}
}

2、在DAL項目中實現IDBSession接口

新建DBSession.tt模板

<#@ template language="C#" debug="false" hostspecific="true"#>
<#@ include file="EF.Utility.CS.ttinclude"#><#@ output extension=".cs"#> 
<#
CodeGenerationTools code = new CodeGenerationTools(this);
MetadataLoader loader = new MetadataLoader(this);
CodeRegion region = new CodeRegion(this, 1);
MetadataTools ef = new MetadataTools(this);
string inputFile = @"..\MODEL\OA.edmx";
EdmItemCollection ItemCollection = loader.CreateEdmItemCollection(inputFile);
string namespaceName = code.VsNamespaceSuggestion();
EntityFrameworkTemplateFileManager fileManager = EntityFrameworkTemplateFileManager.Create(this);
#>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using IDAL;

namespace DAL
{
public partial class DBSession:IDBSession
{
<#
int index=0;
    // Emit Entity Types
foreach (EntityType entity in ItemCollection.GetItems<EntityType>().OrderBy(e => e.Name))
{
index++;
#>
    #region <#=index #> 數據接口 I<#=entity.Name#>DAL
   I<#=entity.Name#>DAL i<#=entity.Name#>DAL;
  public I<#=entity.Name#>DAL I<#=entity.Name#>DAL{
   get
   {
   if(i<#=entity.Name#>DAL==null)
      i<#=entity.Name#>DAL=new <#=entity.Name#>DAL();
      return  i<#=entity.Name#>DAL;
   }
   set
   {
    i<#=entity.Name#>DAL=value;
   }
   }
   #endregion

<#}#>
}
}

Ctrl+S后自動生成DBSession類

 
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using IDAL;

namespace DAL
{
public partial class DBSession:IDBSession
{
    #region 1 數據接口 IBill_LeaveDAL
   IBill_LeaveDAL iBill_LeaveDAL;
  public IBill_LeaveDAL IBill_LeaveDAL{
   get
   {
   if(iBill_LeaveDAL==null)
      iBill_LeaveDAL=new Bill_LeaveDAL();
      return  iBill_LeaveDAL;
   }
   set
   {
    iBill_LeaveDAL=value;
   }
   }
   #endregion

    #region 2 數據接口 IoldWF_AutoTransactNodeDAL
   IoldWF_AutoTransactNodeDAL ioldWF_AutoTransactNodeDAL;
  public IoldWF_AutoTransactNodeDAL IoldWF_AutoTransactNodeDAL{
   get
   {
   if(ioldWF_AutoTransactNodeDAL==null)
      ioldWF_AutoTransactNodeDAL=new oldWF_AutoTransactNodeDAL();
      return  ioldWF_AutoTransactNodeDAL;
   }
   set
   {
    ioldWF_AutoTransactNodeDAL=value;
   }
   }
   #endregion

    #region 3 數據接口 IoldWF_BillFlowNodeDAL
   IoldWF_BillFlowNodeDAL ioldWF_BillFlowNodeDAL;
  public IoldWF_BillFlowNodeDAL IoldWF_BillFlowNodeDAL{
   get
   {
   if(ioldWF_BillFlowNodeDAL==null)
      ioldWF_BillFlowNodeDAL=new oldWF_BillFlowNodeDAL();
      return  ioldWF_BillFlowNodeDAL;
   }
   set
   {
    ioldWF_BillFlowNodeDAL=value;
   }
   }
   #endregion

    #region 4 數據接口 IoldWF_BillFlowNodeRemarkDAL
   IoldWF_BillFlowNodeRemarkDAL ioldWF_BillFlowNodeRemarkDAL;
  public IoldWF_BillFlowNodeRemarkDAL IoldWF_BillFlowNodeRemarkDAL{
   get
   {
   if(ioldWF_BillFlowNodeRemarkDAL==null)
      ioldWF_BillFlowNodeRemarkDAL=new oldWF_BillFlowNodeRemarkDAL();
      return  ioldWF_BillFlowNodeRemarkDAL;
   }
   set
   {
    ioldWF_BillFlowNodeRemarkDAL=value;
   }
   }
   #endregion

    #region 5 數據接口 IoldWF_BillStateDAL
   IoldWF_BillStateDAL ioldWF_BillStateDAL;
  public IoldWF_BillStateDAL IoldWF_BillStateDAL{
   get
   {
   if(ioldWF_BillStateDAL==null)
      ioldWF_BillStateDAL=new oldWF_BillStateDAL();
      return  ioldWF_BillStateDAL;
   }
   set
   {
    ioldWF_BillStateDAL=value;
   }
   }
   #endregion

    #region 6 數據接口 IoldWF_NodeDAL
   IoldWF_NodeDAL ioldWF_NodeDAL;
  public IoldWF_NodeDAL IoldWF_NodeDAL{
   get
   {
   if(ioldWF_NodeDAL==null)
      ioldWF_NodeDAL=new oldWF_NodeDAL();
      return  ioldWF_NodeDAL;
   }
   set
   {
    ioldWF_NodeDAL=value;
   }
   }
   #endregion

    #region 7 數據接口 IoldWF_NodeStateDAL
   IoldWF_NodeStateDAL ioldWF_NodeStateDAL;
  public IoldWF_NodeStateDAL IoldWF_NodeStateDAL{
   get
   {
   if(ioldWF_NodeStateDAL==null)
      ioldWF_NodeStateDAL=new oldWF_NodeStateDAL();
      return  ioldWF_NodeStateDAL;
   }
   set
   {
    ioldWF_NodeStateDAL=value;
   }
   }
   #endregion

    #region 8 數據接口 IoldWF_WorkFlowDAL
   IoldWF_WorkFlowDAL ioldWF_WorkFlowDAL;
  public IoldWF_WorkFlowDAL IoldWF_WorkFlowDAL{
   get
   {
   if(ioldWF_WorkFlowDAL==null)
      ioldWF_WorkFlowDAL=new oldWF_WorkFlowDAL();
      return  ioldWF_WorkFlowDAL;
   }
   set
   {
    ioldWF_WorkFlowDAL=value;
   }
   }
   #endregion

    #region 9 數據接口 IoldWF_WorkFlowNodeDAL
   IoldWF_WorkFlowNodeDAL ioldWF_WorkFlowNodeDAL;
  public IoldWF_WorkFlowNodeDAL IoldWF_WorkFlowNodeDAL{
   get
   {
   if(ioldWF_WorkFlowNodeDAL==null)
      ioldWF_WorkFlowNodeDAL=new oldWF_WorkFlowNodeDAL();
      return  ioldWF_WorkFlowNodeDAL;
   }
   set
   {
    ioldWF_WorkFlowNodeDAL=value;
   }
   }
   #endregion

    #region 10 數據接口 IOu_DepartmentDAL
   IOu_DepartmentDAL iOu_DepartmentDAL;
  public IOu_DepartmentDAL IOu_DepartmentDAL{
   get
   {
   if(iOu_DepartmentDAL==null)
      iOu_DepartmentDAL=new Ou_DepartmentDAL();
      return  iOu_DepartmentDAL;
   }
   set
   {
    iOu_DepartmentDAL=value;
   }
   }
   #endregion

    #region 11 數據接口 IOu_PermissionDAL
   IOu_PermissionDAL iOu_PermissionDAL;
  public IOu_PermissionDAL IOu_PermissionDAL{
   get
   {
   if(iOu_PermissionDAL==null)
      iOu_PermissionDAL=new Ou_PermissionDAL();
      return  iOu_PermissionDAL;
   }
   set
   {
    iOu_PermissionDAL=value;
   }
   }
   #endregion

    #region 12 數據接口 IOu_RoleDAL
   IOu_RoleDAL iOu_RoleDAL;
  public IOu_RoleDAL IOu_RoleDAL{
   get
   {
   if(iOu_RoleDAL==null)
      iOu_RoleDAL=new Ou_RoleDAL();
      return  iOu_RoleDAL;
   }
   set
   {
    iOu_RoleDAL=value;
   }
   }
   #endregion

    #region 13 數據接口 IOu_RolePermissionDAL
   IOu_RolePermissionDAL iOu_RolePermissionDAL;
  public IOu_RolePermissionDAL IOu_RolePermissionDAL{
   get
   {
   if(iOu_RolePermissionDAL==null)
      iOu_RolePermissionDAL=new Ou_RolePermissionDAL();
      return  iOu_RolePermissionDAL;
   }
   set
   {
    iOu_RolePermissionDAL=value;
   }
   }
   #endregion

    #region 14 數據接口 IOu_UserInfoDAL
   IOu_UserInfoDAL iOu_UserInfoDAL;
  public IOu_UserInfoDAL IOu_UserInfoDAL{
   get
   {
   if(iOu_UserInfoDAL==null)
      iOu_UserInfoDAL=new Ou_UserInfoDAL();
      return  iOu_UserInfoDAL;
   }
   set
   {
    iOu_UserInfoDAL=value;
   }
   }
   #endregion

    #region 15 數據接口 IOu_UserRoleDAL
   IOu_UserRoleDAL iOu_UserRoleDAL;
  public IOu_UserRoleDAL IOu_UserRoleDAL{
   get
   {
   if(iOu_UserRoleDAL==null)
      iOu_UserRoleDAL=new Ou_UserRoleDAL();
      return  iOu_UserRoleDAL;
   }
   set
   {
    iOu_UserRoleDAL=value;
   }
   }
   #endregion

    #region 16 數據接口 IOu_UserVipPermissionDAL
   IOu_UserVipPermissionDAL iOu_UserVipPermissionDAL;
  public IOu_UserVipPermissionDAL IOu_UserVipPermissionDAL{
   get
   {
   if(iOu_UserVipPermissionDAL==null)
      iOu_UserVipPermissionDAL=new Ou_UserVipPermissionDAL();
      return  iOu_UserVipPermissionDAL;
   }
   set
   {
    iOu_UserVipPermissionDAL=value;
   }
   }
   #endregion

    #region 17 數據接口 IW_WorkFlowDAL
   IW_WorkFlowDAL iW_WorkFlowDAL;
  public IW_WorkFlowDAL IW_WorkFlowDAL{
   get
   {
   if(iW_WorkFlowDAL==null)
      iW_WorkFlowDAL=new W_WorkFlowDAL();
      return  iW_WorkFlowDAL;
   }
   set
   {
    iW_WorkFlowDAL=value;
   }
   }
   #endregion

    #region 18 數據接口 IW_WorkFlowBranchDAL
   IW_WorkFlowBranchDAL iW_WorkFlowBranchDAL;
  public IW_WorkFlowBranchDAL IW_WorkFlowBranchDAL{
   get
   {
   if(iW_WorkFlowBranchDAL==null)
      iW_WorkFlowBranchDAL=new W_WorkFlowBranchDAL();
      return  iW_WorkFlowBranchDAL;
   }
   set
   {
    iW_WorkFlowBranchDAL=value;
   }
   }
   #endregion

    #region 19 數據接口 IW_WorkFlowNodeDAL
   IW_WorkFlowNodeDAL iW_WorkFlowNodeDAL;
  public IW_WorkFlowNodeDAL IW_WorkFlowNodeDAL{
   get
   {
   if(iW_WorkFlowNodeDAL==null)
      iW_WorkFlowNodeDAL=new W_WorkFlowNodeDAL();
      return  iW_WorkFlowNodeDAL;
   }
   set
   {
    iW_WorkFlowNodeDAL=value;
   }
   }
   #endregion

    #region 20 數據接口 IW_WrokFlowRoleDAL
   IW_WrokFlowRoleDAL iW_WrokFlowRoleDAL;
  public IW_WrokFlowRoleDAL IW_WrokFlowRoleDAL{
   get
   {
   if(iW_WrokFlowRoleDAL==null)
      iW_WrokFlowRoleDAL=new W_WrokFlowRoleDAL();
      return  iW_WrokFlowRoleDAL;
   }
   set
   {
    iW_WrokFlowRoleDAL=value;
   }
   }
   #endregion

    #region 21 數據接口 IWR_WorkFlowApplyDAL
   IWR_WorkFlowApplyDAL iWR_WorkFlowApplyDAL;
  public IWR_WorkFlowApplyDAL IWR_WorkFlowApplyDAL{
   get
   {
   if(iWR_WorkFlowApplyDAL==null)
      iWR_WorkFlowApplyDAL=new WR_WorkFlowApplyDAL();
      return  iWR_WorkFlowApplyDAL;
   }
   set
   {
    iWR_WorkFlowApplyDAL=value;
   }
   }
   #endregion

    #region 22 數據接口 IWR_WrokFlowApplyDetailsDAL
   IWR_WrokFlowApplyDetailsDAL iWR_WrokFlowApplyDetailsDAL;
  public IWR_WrokFlowApplyDetailsDAL IWR_WrokFlowApplyDetailsDAL{
   get
   {
   if(iWR_WrokFlowApplyDetailsDAL==null)
      iWR_WrokFlowApplyDetailsDAL=new WR_WrokFlowApplyDetailsDAL();
      return  iWR_WrokFlowApplyDetailsDAL;
   }
   set
   {
    iWR_WrokFlowApplyDetailsDAL=value;
   }
   }
   #endregion

}
}

接下來，我們創建DBSession工廠和上下文工廠，目的是為了提高效率，在線程中共用一個對象。

3、IDAL項目中添加IDBSessionFactory接口

namespace IDAL
{
    /// <summary>
    /// 數據倉儲工廠
    /// </summary>
   public interface IDBSessionFactory
    {
       IDBSession GetDBSession();
    }
}

DAL項目中添加DBSessionFactory類繼承IDBSessionFactory接口

using System.Runtime.Remoting.Messaging;
using IDAL;

namespace DAL
{
    public class DBSessionFactory : IDBSessionFactory
    {
        /// <summary>
        /// 此方法的作用： 提高效率，在線程中 共用一個 DBSession 對象！
        /// </summary>
        /// <returns></returns>
        public IDBSession GetDBSession()
        {
            //從當前線程中 獲取 DBContext 數據倉儲 對象
            IDBSession dbSesion = CallContext.GetData(typeof(DBSessionFactory).Name) as DBSession;
            if (dbSesion == null)
            {
                dbSesion = new DBSession();
                CallContext.SetData(typeof(DBSessionFactory).Name, dbSesion);
            }
            return dbSesion;
        }
    }
}

4、同樣，我們再來創建一個上下文工廠，即便以后有多個數據庫上下文，也能夠很好的支持。

IDAL項目中，新建IDBContextFactory.cs接口

using System.Data.Entity;

namespace IDAL
{
    /// <summary>
    /// EF數據上下文 工廠
    /// </summary>
   public interface IDBContextFactory
    {
       /// <summary>
        /// 獲取 EF 上下文對象
       /// </summary>
       /// <returns></returns>
       DbContext GetDbContext();
    }

DAL項目中新建DBContextFactory類繼承IDBContextFactory接口

using System.Data.Entity;
using System.Runtime.Remoting.Messaging;
using Model;

namespace DAL
{
    public class DBContextFactory : IDBContextFactory
    {
        #region 創建 EF上下文 對象，在線程中共享 一個 上下文對象 + DbContext GetDbContext()
        /// <summary>
        /// 創建 EF上下文 對象，在線程中共享 一個 上下文對象
        /// </summary>
        /// <returns></returns>
        public DbContext GetDbContext()
        {
            ////從當前線程中 獲取 EF上下文對象
            var dbContext = CallContext.GetData(typeof(DBContextFactory).Name) as DbContext;
            if (dbContext == null)
            {
                dbContext = new OAEntities();
                CallContext.SetData(typeof(DBContextFactory).Name, dbContext);
            }
            return dbContext;
        }
        #endregion
    }
}

5、Common項目中，添加ConfigurationHelper.cs來操作配置文件

using System;
using System.Configuration;

namespace Common
{
    public static class ConfigurationHelper
    {
        public static string AppSetting(string key)
        {
            return ConfigurationManager.AppSettings[key];
        }
    }
}

Web.config中添加如下配置節點：

    <add key="DBSessionFatory" value="DAL.DBSessionFactory" />
    <add key="DBSessionFatoryDLL" value="E:\WorkSpace\Study\Webs\MVC\OAsln\Web\bin\DAL.dll" />

6、修改BaseBLL類的調用方式，添加如下代碼：

        /// <summary>
        /// 2.0 數據倉儲接口（相當於數據層工廠，可以創建所有的數據子類對象）
        /// </summary>
        private IDAL.IDBSession iDbSession;

        #region 數據倉儲 屬性 + IDBSession DBSession
        /// <summary>
        /// 數據倉儲 屬性
        /// </summary>
        public IDAL.IDBSession DBSession
        {
            get
            {
                if (iDbSession == null)
                {
                    //1.讀取配置文件
                    string strFactoryDLL = Common.ConfigurationHelper.AppSetting("DBSessionFatoryDLL");
                    string strFactoryType = Common.ConfigurationHelper.AppSetting("DBSessionFatory");
                    //2.1通過反射創建 DBSessionFactory 工廠對象
                    Assembly dalDLL = Assembly.LoadFrom(strFactoryDLL);
                    Type typeDBSessionFatory = dalDLL.GetType(strFactoryType);
                    IDAL.IDBSessionFactory sessionFactory = Activator.CreateInstance(typeDBSessionFatory) as IDAL.IDBSessionFactory;
                    //2.2根據配置文件內容 使用 DI層里的Spring.Net 創建 DBSessionFactory 工廠對象


                    //3.通過 工廠 創建 DBSession對象
                    iDbSession = sessionFactory.GetDBSession();
                }
                return iDbSession;
            }
        }
        #endregion

 在這里，使用到了工廠來創建對象，后面引入了Spring.net之后，會回過頭來優化現有的代碼。項目中使用到了許多接口，目的是為了解耦，每一個項目的職責盡量讓其單一，業務層只讓其調用數據層接口，也是為了依賴於抽象，而不是具體。每一個框架其實都是各種設計模式的一個集合，設計模式是為了解決一類問題，而框架就是為了解決一系列問題了。到現在為止，整個項目的雛形已經出來了，但是后續，我們一步一步來優化，好的框架不是一下子就能設計得完美的，而是能夠不斷的擁抱修改，可持續擴展，不斷改進出來的。