本文主要是介绍OLE DB备考，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
请输入大于10个字符的资源描述表对应部分，使用VC属性概念，参考wizard创建的代码制作表的类。
#pragma once [ db_table(L " T_Event " )] class CT_Event
... {
public: [db_column(1, status=m_dwEvent_IDStatus, length=m_dwEvent_IDLength)] LONG m_Event_ID; [db_column(2, status=m_dwEvent_ContentStatus, length=m_dwEvent_ContentLength)] TCHAR m_Event_Content[255]; [db_column(3, status=m_dwEvent_ExecutorStatus, length=m_dwEvent_ExecutorLength)] TCHAR m_Event_Executor[20]; [db_column(4, status=m_dwEvent_StartTimeStatus, length=m_dwEvent_StartTimeLength)] DATE m_Event_StartTime; [db_column(5, status=m_dwEvent_EndTimeStatus, length=m_dwEvent_EndTimeLength)] DATE m_Event_EndTime; [db_column(6, status=m_dwEvent_PrivacyStatus, length=m_dwEvent_PrivacyLength)] LONG m_Event_Privacy; [db_column(7, status=m_dwEvent_GroupStatus, length=m_dwEvent_GroupLength)] TCHAR m_Event_Group[20]; [db_column(8, status=m_dwEvent_CreatorStatus, length=m_dwEvent_CreatorLength)] TCHAR m_Event_Creator[20]; [db_column(9, status=m_dwEvent_CreateTimeStatus, length=m_dwEvent_CreateTimeLength)] DATE m_Event_CreateTime; [db_column(10, status=m_dwEvent_UpdaterStatus, length=m_dwEvent_UpdaterLength)] TCHAR m_Event_Updater[20]; [db_column(11, status=m_dwEvent_UpdateTimeStatus, length=m_dwEvent_UpdateTimeLength)] DATE m_Event_UpdateTime; [db_column(12, status=m_dwEvent_DeleteFlagStatus, length=m_dwEvent_DeleteFlagLength)] VARIANT_BOOL m_Event_DeleteFlag; [db_column(13, status=m_dwEvent_AddressStatus, length=m_dwEvent_AddressLength)] TCHAR m_Event_Address[255]; [db_column(14, status=m_dwEvent_CommentStatus, length=m_dwEvent_CommentLength)] TCHAR m_Event_Comment[255]; [db_column(15, status=m_dwEvent_AllDayFlagStatus, length=m_dwEvent_AllDayFlagLength)] VARIANT_BOOL m_Event_AllDayFlag; [db_column(16, status=m_dwEvent_LoopTypeStatus, length=m_dwEvent_LoopTypeLength)] LONG m_Event_LoopType; DBSTATUS m_dwEvent_IDStatus; DBSTATUS m_dwEvent_ContentStatus; DBSTATUS m_dwEvent_ExecutorStatus; DBSTATUS m_dwEvent_StartTimeStatus; DBSTATUS m_dwEvent_EndTimeStatus; DBSTATUS m_dwEvent_PrivacyStatus; DBSTATUS m_dwEvent_GroupStatus; DBSTATUS m_dwEvent_CreatorStatus; DBSTATUS m_dwEvent_CreateTimeStatus; DBSTATUS m_dwEvent_UpdaterStatus; DBSTATUS m_dwEvent_UpdateTimeStatus; DBSTATUS m_dwEvent_DeleteFlagStatus; DBSTATUS m_dwEvent_AddressStatus; DBSTATUS m_dwEvent_CommentStatus; DBSTATUS m_dwEvent_AllDayFlagStatus; DBSTATUS m_dwEvent_LoopTypeStatus; DBLENGTH m_dwEvent_IDLength; DBLENGTH m_dwEvent_ContentLength; DBLENGTH m_dwEvent_ExecutorLength; DBLENGTH m_dwEvent_StartTimeLength; DBLENGTH m_dwEvent_EndTimeLength; DBLENGTH m_dwEvent_PrivacyLength; DBLENGTH m_dwEvent_GroupLength; DBLENGTH m_dwEvent_CreatorLength; DBLENGTH m_dwEvent_CreateTimeLength; DBLENGTH m_dwEvent_UpdaterLength; DBLENGTH m_dwEvent_UpdateTimeLength; DBLENGTH m_dwEvent_DeleteFlagLength; DBLENGTH m_dwEvent_AddressLength; DBLENGTH m_dwEvent_CommentLength; DBLENGTH m_dwEvent_AllDayFlagLength; DBLENGTH m_dwEvent_LoopTypeLength; void GetRowsetProperties(CDBPropSet* pPropSet)
...{ pPropSet->AddProperty(DBPROP_CANFETCHBACKWARDS, true, DBPROPOPTIONS_OPTIONAL); pPropSet->AddProperty(DBPROP_CANSCROLLBACKWARDS, true, DBPROPOPTIONS_OPTIONAL); pPropSet->AddProperty(DBPROP_IRowsetChange, true, DBPROPOPTIONS_OPTIONAL); pPropSet->AddProperty(DBPROP_UPDATABILITY, DBPROPVAL_UP_CHANGE | DBPROPVAL_UP_INSERT | DBPROPVAL_UP_DELETE);
} HRESULT OpenDataSource(LPCTSTR szDatabasePath) ...{ CDataSource _db; HRESULT hr; WCHAR* szPath;#if !defined UNICODE || _UNICODE USES_CONVERSION; szPath = A2W(szDatabasePath);#else szPath = szDatabasePath;#endif const WCHAR strnn[] = L"Provider=Microsoft.Jet.OLEDB.4.0;Data Source="; unsigned int nlen = sizeof(strnn) + sizeof(szPath) + 1; WCHAR* strdb = new WCHAR[nlen]; wcscpy(strdb, strnn); wcscat(strdb, szPath); hr = _db.OpenFromInitializationString(strdb); delete strdb; if (FAILED(hr)) ...{#ifdef _DEBUG AtlTraceErrorRecords(hr);#endif return hr; } return m_session.Open(_db); } void CloseDataSource() ...{ m_session.Close(); } operator const CSession&() ...{ return m_session; } CSession m_session;
} ; MFC 外带ATL支持，这是stdafx.h
// stdafx.h : include file for standard system include files, // or project specific include files that are used frequently, but // are changed infrequently // #pragma once #ifndef _WIN32_WINNT #define _WIN32_WINNT 0x0500 #endif #include < iostream > #include < tchar.h > #define _ATL_CSTRING_EXPLICIT_CONSTRUCTORS // some CString constructors will be explicit #ifndef VC_EXTRALEAN #define VC_EXTRALEAN // Exclude rarely-used stuff from Windows headers #endif #include < afx.h > #include < afxwin.h > // MFC core and standard components #include < afxext.h > // MFC extensions #include < afxdtctl.h > // MFC support for Internet Explorer 4 Common Controls #ifndef _AFX_NO_AFXCMN_SUPPORT#include < afxcmn.h > // MFC support for Windows Common Controls #endif // _AFX_NO_AFXCMN_SUPPORT #define _ATL_CSTRING_EXPLICIT_CONSTRUCTORS // some CString constructors will be explicit #include < atlbase.h > #include < atldbcli.h > // TODO: reference additional headers your program requires here // #define CONNSTRING(X) "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" #X " " 主要的部分AccessAgent，使用这个类来操作Access数据库
#pragma once #include < atldbcli.h > class CAccessAgent ... {public: CAccessAgent(); CAccessAgent(LPCTSTR szDatabasePath); static BOOL CreateAccessDatabase(LPCTSTR szDatabasePath); //second parameter is SQL statement //it is used for creating tables and views //CCommand in the function has not Accessor, maybe needs CCommand<CDynamicAccessor> in future static BOOL ExecuteSQL(LPCTSTR szDatabasePath, LPCTSTR lpsz); int ExecuteSQL(LPCTSTR lpsz);private: CString m_errstr; HRESULT m_hr; //db_source and db_session CDataSource m_conn; CSession m_session;} ; #include " stdafx.h " #include " AccessAgent.h " CAccessAgent::CAccessAgent() ... {} CAccessAgent:: ~ CAccessAgent() ... { m_session.Close(); m_conn.Close();} CAccessAgent::CAccessAgent(LPCTSTR szDatabasePath) ... { WCHAR* szPath;#if !defined UNICODE || _UNICODE USES_CONVERSION; szPath = A2W(szDatabasePath);#else szPath = szDatabasePath;#endif const WCHAR strnn[] = L"Provider=Microsoft.Jet.OLEDB.4.0;Data Source="; unsigned int nlen = sizeof(strnn) + sizeof(szPath) + 1; WCHAR* strdb = new WCHAR[nlen]; wcscpy(strdb, strnn); wcscat(strdb, szPath); HRESULT hr = m_conn.OpenFromInitializationString(strdb); delete strdb; if(SUCCEEDED(hr)) ...{ hr = m_session.Open(m_conn); if(FAILED(hr)) ...{ m_hr = hr; m_session.Close(); m_conn.Close(); } } else ...{ m_hr = hr; m_conn.Close(); }} BOOL CAccessAgent::CreateAccessDatabase(LPCTSTR szDatabasePath) ... { CDataSource ds; IDBDataSourceAdmin* pIDBDataSourceAdmin = NULL; CLSID clsid = ...{0xdee35070L,0x506b,0x11cf, ...{0xb1,0xaa,0x0,0xaa,0x0,0xb8,0xde,0x95}}; HRESULT hr = CoCreateInstance(clsid, NULL, CLSCTX_INPROC_SERVER, __uuidof(IDBInitialize), (void**)&ds.m_spInit); if (FAILED(hr)) return FALSE; USES_CONVERSION; CDBPropSet rgPropertySet(DBPROPSET_DBINIT); rgPropertySet.AddProperty(DBPROP_INIT_DATASOURCE, T2BSTR(szDatabasePath)); hr = ds.m_spInit->QueryInterface(IID_IDBDataSourceAdmin, (void**)&pIDBDataSourceAdmin); if(FAILED(hr)) ...{ ds.Close(); return FALSE; } hr = pIDBDataSourceAdmin->CreateDataSource(1, &rgPropertySet, NULL, IID_NULL, NULL); if(FAILED(hr)) ...{ pIDBDataSourceAdmin->Release(); ds.Close(); return FALSE; } pIDBDataSourceAdmin->Release(); ds.Close(); return TRUE;} BOOL CAccessAgent::ExecuteSQL(LPCTSTR szDatabasePath, LPCTSTR lpsz) ... { HRESULT hr; CDataSource ds; CSession session; CCommand<CDynamicAccessor> comm; WCHAR* szPath;#if !defined UNICODE || _UNICODE USES_CONVERSION; szPath = A2W(szDatabasePath);#else szPath = szDatabasePath;#endif const WCHAR strnn[] = L"Provider=Microsoft.Jet.OLEDB.4.0;Data Source="; unsigned int nlen = sizeof(strnn) + sizeof(szPath) + 1; WCHAR* strdb = new WCHAR[nlen]; wcscpy(strdb, strnn); wcscat(strdb, szPath); hr = ds.OpenFromInitializationString(strdb); delete strdb; if(FAILED(hr)) ...{ ds.Close(); return FALSE; } hr = session.Open(ds); if(FAILED(hr)) ...{ session.Close(); ds.Close(); return FALSE; } hr = comm.Create(session, lpsz, DBGUID_DBSQL); if(SUCCEEDED(hr)) ...{ CDBPropSet propset(DBPROPSET_ROWSET); propset.AddProperty(DBPROP_IRowsetChange, true); propset.AddProperty(DBPROP_UPDATABILITY, DBPROPVAL_UP_CHANGE | DBPROPVAL_UP_INSERT | DBPROPVAL_UP_DELETE); hr = comm.Open(&propset, NULL, false, 0); if(FAILED(hr)) ...{ comm.Close(); session.Close(); ds.Close(); return FALSE; } } else ...{ comm.Close(); session.Close(); ds.Close(); return FALSE; } comm.Close(); session.Close(); ds.Close(); return TRUE;} BOOL CAccessAgent::ExecuteSQL(LPCTSTR lpsz) ... { BOOL ret = TRUE; HRESULT hr; CCommand<CDynamicAccessor> comm; hr = comm.Create(m_session, lpsz, DBGUID_DBSQL); if(SUCCEEDED(hr)) ...{ CDBPropSet propset(DBPROPSET_ROWSET); propset.AddProperty(DBPROP_IRowsetChange, true); propset.AddProperty(DBPROP_UPDATABILITY, DBPROPVAL_UP_CHANGE | DBPROPVAL_UP_INSERT | DBPROPVAL_UP_DELETE); hr = comm.Open(&propset, NULL, false, 0); if (FAILED(hr)) ...{ ret = FALSE; m_hr = hr; } } else ...{ ret = FALSE; m_hr = hr; } comm.Close(); return ret;} 程序启动点
// AccessManipulator.cpp : Defines the entry point for the console application. // #include " stdafx.h " #include " AccessManipulator.h " #ifdef _DEBUG #define new DEBUG_NEW #endif #include " AccessAgent.h " #include " T_Event.h " // The one and only application object CWinApp theApp; using namespace std; int _tmain( int argc, TCHAR * argv[], TCHAR * envp[]) ... { int nRetCode = 0; // initialize MFC and print and error on failure if (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(), 0)) ...{ // TODO: change error code to suit your needs _tprintf(_T("Fatal Error: MFC initialization failed ")); nRetCode = 1; } else ...{ HRESULT hr = S_OK; CString dbPath = "../AccessTest.mdb";#ifdef _DEBUG CFileFind finder; BOOL bWorking = finder.FindFile(dbPath.GetBuffer()); if (bWorking) ...{ ::DeleteFile(dbPath.GetBuffer()); } else printf("delete mdb file failed! ");#endif //init COM Interface hr = CoInitialize(NULL); if(FAILED(hr)) ...{ printf("COM initialzing failed! "); } if(!CAccessAgent::CreateAccessDatabase(dbPath.GetBuffer())) ...{ printf("create database failed! "); } //create table, //do the same way, when creating your views. CAccessAgent agent(dbPath.GetBuffer()); CString strSqlCreateEventTable = "CREATE TABLE T_Event( Event_ID INTEGER, Event_Content TEXT(255), Event_Executor CHAR(20), Event_StartTime DATETIME, Event_EndTime DATETIME, Event_Privacy INTEGER, Event_Group CHAR(20), Event_Creator CHAR(20), Event_CreateTime DATETIME, Event_Updater CHAR(20), Event_UpdateTime DATETIME, Event_DeleteFlag BIT, Event_Address TEXT(255), Event_Comment TEXT(255), Event_AllDayFlag BIT, Event_LoopType INTEGER )"; if(!agent.ExecuteSQL(strSqlCreateEventTable.GetBuffer())) ...{ printf("create event table failed! "); } //example for inserting into and reading from T_Event CT_Event event; event.OpenDataSource(dbPath); hr = event.OpenRowset(event); //event.m_Event_ID = 1; //_tcscpy(event.m_Event_Content, "qwieojaodjfoaiwejrower"); //_tcscpy(event.m_Event_Executor, "qwieojaodjfoaiwejrower"); //event.m_Event_StartTime = 12.00; //event.m_Event_EndTime = 1.00; //event.m_Event_Privacy = 123123; //_tcscpy(event.m_Event_Group, "qwieojaodjfoaiwejrower"); //hr = event.Insert(); //event.MoveNext(); //hr = event.GetData(); //printf("%d, %s ", event.m_Event_ID, event.m_Event_Content); event.CloseDataSource(); } //Uninit COM Interface CoUninitialize(); getchar(); return nRetCode;} 这篇关于OLE DB备考的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！
