实战COM(09)----COM+的特性之对象池

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                     实战COM(09)----COM+的特性之对象池

    本节我们将上一节的组件改造成可池化的组件。修改如下：一、修改组件1)头文件Simple05.h// Simple05.h : Declaration of the CSimple05

#ifndef __SIMPLE05_H_#define __SIMPLE05_H_

#include "resource.h"       // main symbols#include <mtx.h>

/// CSimple05class ATL_NO_VTABLE CSimple05 :  public CComObjectRootEx<CComMultiThreadModel>, public CComCoClass<CSimple05, &CLSID_Simple05>, public IObjectControl,  // 支持对象池操作 public ISimple05{public: CSimple05() { }

DECLARE_REGISTRY_RESOURCEID(IDR_SIMPLE05)

DECLARE_PROTECT_FINAL_CONSTRUCT()

BEGIN_COM_MAP(CSimple05) COM_INTERFACE_ENTRY(ISimple05) COM_INTERFACE_ENTRY(IObjectControl)END_COM_MAP()

// IObjectControlpublic: STDMETHOD(Activate)(); STDMETHOD_(BOOL, CanBePooled)(); STDMETHOD_(void, Deactivate)();

 CComPtr<IObjectContext> m_spObjectContext;

// ISimple05public: STDMETHOD(ModifyData)();};

#endif //__SIMPLE05_H_

2)应用文件Simple05.cpp// Simple05.cpp : Implementation of CSimple05#include "stdafx.h"#include "Step05.h"#include "Simple05.h"

#include <mtx.h>    // 事务支持#include <atldbcli.h>    // 数据库操作 // 加入comutil支持#include <comutil.h>#pragma comment( lib, "comsupp.lib" )

/// CSimple05

// 定义一个新类class CAuthors{public: // 数据--宽度来源于表Authors char m_szAu_Id[12];   char m_szAu_lName[41];  // 参数绑定 BEGIN_PARAM_MAP(CAuthors)  COLUMN_ENTRY(1, m_szAu_lName)  COLUMN_ENTRY(2, m_szAu_Id) END_PARAM_MAP()};

STDMETHODIMP CSimple05::ModifyData(){ CDataSource Connection; CSession Session; CCommand<CAccessor<CAuthors> > Authors; HRESULT  hr;

 // 创建一个事务 //IObjectContext* pObjectContext = NULL; //hr = GetObjectContext(&pObjectContext); //if(FAILED(hr) || ! pObjectContext) return hr;

 // 检查是否存在事务环境 //if(! pObjectContext->IsInTransaction()) return E_FAIL;

 // 打开数据库 CDBPropSet dbinit(DBPROPSET_DBINIT); dbinit.AddProperty(DBPROP_INIT_DATASOURCE, OLESTR("GP2000"));   // 服务器名 dbinit.AddProperty(DBPROP_AUTH_USERID, OLESTR("sa"));    // 用户名 dbinit.AddProperty(DBPROP_AUTH_PASSWORD, OLESTR("123"));   // 密码 dbinit.AddProperty(DBPROP_AUTH_PERSIST_SENSITIVE_AUTHINFO, false); dbinit.AddProperty(DBPROP_INIT_CATALOG, OLESTR("pubs"));   // 数据库名 dbinit.AddProperty(DBPROP_INIT_LCID, (long)2052); dbinit.AddProperty(DBPROP_INIT_PROMPT, (short)4); hr = Connection.Open(_T("SQLOLEDB.1"), &dbinit); if (FAILED(hr)) return hr;  hr = Session.Open(Connection); if (FAILED(hr))  {  Connection.Close();  return hr; } // 设置更新条件   strcpy(Authors.m_szAu_Id,    "172-32-1176"); // 172-32-1176 strcpy(Authors.m_szAu_lName, "MY name");  // White hr = Authors.Open(Session, "Update Authors Set Au_lName = ? Where Au_Id = ?");  //if(pObjectContext) //{  if(SUCCEEDED(hr))  {   m_spObjectContext->SetComplete(); // 提交事务  }  else  {   m_spObjectContext->SetAbort();  } //}

 Session.Close(); Connection.Close();

 return hr;}// 对象池操作HRESULT CSimple05::Activate(){ HRESULT hr = GetObjectContext(&m_spObjectContext); if (SUCCEEDED(hr))  return S_OK; return hr;}

BOOL CSimple05::CanBePooled(){ return TRUE;}

void CSimple05::Deactivate(){ m_spObjectContext.Release();}

二、配置对象池1)从管理工具打开“组件服务”，删除并重新安装组件“Step05.Simple05.1”组件2)设置“Step05.Simple05.1”属性，如下图，