簡單的 C++ 操作資料庫類
阿新 • • 發佈：2019-02-05
網上看到的一個 C++ 操作資料庫的類，記錄下來。
AdoConnection.h
#ifndef __AdoConnection_h__ #define __AdoConnection_h__ class CAdoRecordset; class CAdoConnection { public: static CAdoConnection* GetAdoConnection(); static void DestroyAdoConnection(); ~CAdoConnection(); BOOL InitInstance(); BOOL Open() const; void Close() const; BOOL IsOpened() const; BOOL GetConnectionIDispatch( _variant_t& vActiveConn ); BOOL OpenRecordset( TCHAR* sqlCmd, CAdoRecordset& recordset ); BOOL ExecuteNonQuery( const TCHAR *sqlcmd ) const; BOOL Execute( const TCHAR *sqlcmd, CAdoRecordset& rst ); private: _ConnectionPtr _ConnPtr; static CAdoConnection* _AdoConnPtr; CAdoConnection(); CAdoConnection( const CAdoConnection& ); CAdoConnection& operator = ( const CAdoConnection& ); }; #endif // __CAdoConnection_h__
AdoConnection.cpp
#include "AdoConnection.h" #include "AdoRecordset.h" CAdoConnection* CAdoConnection::_AdoConnPtr = NULL; CAdoConnection* CAdoConnection::GetAdoConnection() { if( NULL == _AdoConnPtr ) { _AdoConnPtr = new CAdoConnection(); if( !_AdoConnPtr->InitInstance() ) return NULL; if( !_AdoConnPtr->Open() ) return NULL; } return _AdoConnPtr; } void CAdoConnection::DestroyAdoConnection() { if( NULL != _AdoConnPtr ) { _AdoConnPtr->Close(); delete _AdoConnPtr; _AdoConnPtr = NULL; } } CAdoConnection::CAdoConnection() { _ConnPtr = NULL; } CAdoConnection::~CAdoConnection() { try { if( IsOpened() ) Close(); } catch( _com_error e ) { CString strErrorMsg; strErrorMsg.Format( _T("AdoConnection析構失敗！\n錯誤資訊: %s"), e.ErrorMessage() ); AfxMessageBox( strErrorMsg ); } } BOOL CAdoConnection::InitInstance() { try { _ConnPtr.CreateInstance( __uuidof(Connection) ); return TRUE; } catch( _com_error e ) { CString strErrorMsg; strErrorMsg.Format( _T("AdoConnection初始化失敗！\n錯誤資訊: %s"), e.ErrorMessage() ); AfxMessageBox( strErrorMsg ); } return FALSE; } BOOL CAdoConnection::Open() const { try { if( IsOpened() ) Close(); if( SUCCEEDED(_ConnPtr->Open( g_DatabaseConnectionString, _T(""), _T(""), adModeUnknown)) ) return TRUE; } catch( _com_error e ) { CString strErrorMsg; strErrorMsg.Format( _T("連線資料庫失敗！\n錯誤資訊: %s"), e.ErrorMessage() ); AfxMessageBox( strErrorMsg ); } return FALSE; } void CAdoConnection::Close() const { try { if( IsOpened() ) _ConnPtr->Close(); } catch( _com_error e ) { CString strErrorMsg; strErrorMsg.Format( _T("斷開資料庫失敗！\n錯誤資訊: %s"), e.ErrorMessage() ); AfxMessageBox( strErrorMsg ); } } BOOL CAdoConnection::IsOpened() const { if( NULL == _ConnPtr ) return FALSE; if( _ConnPtr->State ) return TRUE; return FALSE; } BOOL CAdoConnection::GetConnectionIDispatch( _variant_t& vActiveConn ) { vActiveConn = (IDispatch*)_ConnPtr; //vActiveConn = _ConnPtr.GetInterfacePtr(); return TRUE; } BOOL CAdoConnection::ExecuteNonQuery( const TCHAR *sqlcmd ) const { try { VARIANT vRecordAffected; VariantInit( &vRecordAffected ); if( IsOpened() ) { _ConnPtr->Execute( (_bstr_t)sqlcmd, &vRecordAffected, adCmdText/*adExecuteNoRecords*/ ); return TRUE; } } catch( _com_error e ) { CString strErrorMsg; strErrorMsg.Format( _T("ExecuteNonQuery失敗！\n錯誤資訊: %s"), e.ErrorMessage() ); AfxMessageBox( strErrorMsg ); } return FALSE; } BOOL CAdoConnection::Execute( const TCHAR *sqlcmd, CAdoRecordset& rst ) { try { const _variant_t strSql = sqlcmd; rst.Close(); rst.Open( sqlcmd, *this ); return TRUE; } catch( _com_error e ) { CString strErrorMsg; strErrorMsg.Format( _T("Execute失敗！\n錯誤資訊: %s"), e.ErrorMessage() ); AfxMessageBox( strErrorMsg ); } return FALSE; } BOOL CAdoConnection::OpenRecordset( TCHAR* sqlCmd, CAdoRecordset& recordset ) { return recordset.Open( sqlCmd, *this ); }
AdoRecordset.h
#ifndef __AdoRecordset_h__ #define __AdoRecordset_h__ class CAdoConnection; class CAdoRecordset { public: CAdoRecordset(); CAdoRecordset( _RecordsetPtr *ptr ); ~CAdoRecordset(); void MoveFirst (); void MoveNext (); void MovePrev (); void MoveLast (); void Move ( int offset ); BOOL Open ( const TCHAR *sql, CAdoConnection& adoConn ); void Close (); BOOL IsOpened (); BOOL IsBOF (); BOOL IsEOF (); int GetFieldCount (); int GetFieldOrder ( const TCHAR *fieldname ); TCHAR* GetFieldName ( const int fieldorder ); TCHAR* GetFieldValueStr ( const int fieldorder ); TCHAR* GetFieldValueStr ( const TCHAR *fieldname ); int GetFieldValueInt ( const int fieldorder ); int GetFieldValueInt ( const TCHAR *fieldname ); float GetFieldValueFlt ( const int fieldorder ); float GetFieldValueFlt ( const TCHAR *fieldname ); BOOL GetFieldValueBool ( const int fieldoerder ); BOOL GetFieldValueBool ( const TCHAR *fieldname ); int GetRecordCount (); private: _RecordsetPtr _Recordset; CAdoRecordset( const CAdoRecordset& ); CAdoRecordset& operator = ( const CAdoRecordset& ); }; #endif // __AdoRecordset_h__
AdoRecordset.cpp
#include "stdafx.h"
#include "AdoRecordset.h"
#include "AdoConnection.h"
CAdoRecordset::CAdoRecordset()
{
try {
_Recordset.CreateInstance( __uuidof(Recordset) );
}
catch( _com_error e ) {
CString strErrorMsg;
strErrorMsg.Format( _T("CAdoRecordset初始化失敗！\n錯誤資訊: %s"), e.ErrorMessage() );
AfxMessageBox( strErrorMsg );
}
}
CAdoRecordset::CAdoRecordset( _RecordsetPtr *ptr )
{
try {
(*ptr).CreateInstance( __uuidof(Recordset) );
_Recordset = *ptr;
}
catch( _com_error e ) {
CString strErrorMsg;
strErrorMsg.Format( _T("CAdoRecordset初始化失敗！\n錯誤資訊: %s"), e.ErrorMessage() );
AfxMessageBox( strErrorMsg );
}
}
CAdoRecordset::~CAdoRecordset()
{
if( IsOpened() )
Close();
}
BOOL CAdoRecordset::Open( const TCHAR *sql, CAdoConnection& adoConn )
{
if( NULL == sql || 0 == _ftcsclen(sql) ) {
AfxMessageBox( _T("Empty Sql statement ！") );
return FALSE;
}
if( !adoConn.IsOpened() ) {
AfxMessageBox( _T("CAdoRecordset::Open: adoConn is not opened !") );
return FALSE;
}
if( _Recordset->State != adStateClosed )
_Recordset->Close();
_variant_t vActiveConn;
if( !adoConn.GetConnectionIDispatch(vActiveConn) ) {
AfxMessageBox( _T("CAdoRecordset::Open: adoConn.GetConnectionIDispatch failed !") );
return FALSE;
}
try {
HRESULT hr = _Recordset->Open( _variant_t(sql), vActiveConn, adOpenStatic/*adOpenKeyset*/,
adLockOptimistic/*adLockReadOnly*/, adCmdUnknown/*adOptionUnspecified*/ );
return SUCCEEDED(hr);
}
catch( _com_error e ) {
CString strErrorMsg;
strErrorMsg.Format( _T("CAdoRecordset::Open()失敗！\n錯誤資訊: %s"), e.ErrorMessage() );
AfxMessageBox( strErrorMsg );
TCHAR *p = (TCHAR*)(e.Description());
AfxMessageBox( p );
}
return FALSE;
}
void CAdoRecordset::Close()
{
if( IsOpened() )
_Recordset->Close();
}
BOOL CAdoRecordset::IsOpened()
{
if( _Recordset->State )
return TRUE;
return FALSE;
}
BOOL CAdoRecordset::IsEOF()
{
BOOL rst = TRUE;
if( IsOpened() )
rst = (BOOL)(_Recordset->GetadoEOF());
return rst;
}
BOOL CAdoRecordset::IsBOF()
{
BOOL rst = TRUE;
if( IsOpened() )
rst = (BOOL)(_Recordset->GetBOF());
return rst;
}
int CAdoRecordset::GetRecordCount()
{
int count = -1;
if( IsOpened() )
count = (int)_Recordset->GetRecordCount();
return count;
}
void CAdoRecordset::MoveFirst()
{
if( IsOpened() )
_Recordset->MoveFirst();
}
void CAdoRecordset::MoveNext()
{
if( IsOpened() )
_Recordset->MoveNext();
}
void CAdoRecordset::MovePrev()
{
if( IsOpened() )
_Recordset->MovePrevious();
}
void CAdoRecordset::MoveLast()
{
if( IsOpened() )
_Recordset->MoveLast();
}
void CAdoRecordset::Move( int offset )
{
if( IsOpened() )
_Recordset->Move( (long)offset );
}
int CAdoRecordset::GetFieldCount()
{
int fieldCount = -1;
if( IsOpened() )
fieldCount = _Recordset->GetFields()->GetCount();
return fieldCount;
}
int CAdoRecordset::GetFieldOrder( const TCHAR* fieldname )
{
int fieldOrder = -1;
if( IsOpened() ) {
int fieldCount = GetFieldCount();
for( int i = 0; i < fieldCount; i++ ) {
if(_Recordset->GetFields()->Item[i]->Name == (_bstr_t)fieldname ) {
fieldOrder = i;
break;
}
}
}
return fieldOrder;
}
TCHAR* CAdoRecordset::GetFieldName( const int fieldorder )
{
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
int fieldCount = _Recordset->GetFields()->GetCount();
if( fieldCount > 0 ) {
if( fieldorder >= 0 && fieldorder < fieldCount )
return (TCHAR*)(_Recordset->GetFields()->Item[fieldorder]->Name);
}
}
}
return NULL;
}
TCHAR* CAdoRecordset::GetFieldValueStr( const int fieldorder )
{
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
int fieldCount = _Recordset->GetFields()->GetCount();
if( fieldCount > 0 ) {
if( fieldorder >= 0 && fieldorder < fieldCount ) {
return (TCHAR*)((_Recordset->GetFields()->Item[fieldorder]->Value).operator _bstr_t());
}
}
}
}
return NULL;
}
TCHAR* CAdoRecordset::GetFieldValueStr( const TCHAR *fieldname )
{
if( IsOpened() ) {
try {
if( NULL != _Recordset->GetFields() )
return (TCHAR*)((_Recordset->Fields->Item[fieldname]->Value).operator _bstr_t());
}
catch( _com_error e ) {
//CString strErrorMsg;
//strErrorMsg.Format( _T("CAdoRecordset初始化失敗！\n錯誤資訊: %s"), e.ErrorMessage() );
//AfxMessageBox( strErrorMsg );
}
}
return NULL;
}
int CAdoRecordset::GetFieldValueInt( const int fieldorder )
{
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
int fieldCount = _Recordset->GetFields()->GetCount();
if( fieldCount > 0 ) {
if( fieldorder >= 0 && fieldorder < fieldCount ) {
return (int)(_Recordset->GetFields()->GetItem(fieldorder)->Value).operator int();
}
}
}
}
return -1;
}
int CAdoRecordset::GetFieldValueInt( const TCHAR *fieldname )
{
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
return (_Recordset->Fields->Item[fieldname]->Value).operator int();
}
}
return -1;
}
float CAdoRecordset::GetFieldValueFlt( const int fieldorder )
{
float ret = -1.0;
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
int fieldCount = _Recordset->GetFields()->GetCount();
if( fieldCount > 0 ) {
if( fieldorder >= 0 && fieldorder < fieldCount ) {
ret = (float)((_Recordset->GetFields()->Item[fieldorder]->Value).operator float());
}
}
}
}
return ret;
}
float CAdoRecordset::GetFieldValueFlt( const TCHAR *fieldname )
{
float ret = -1.0;
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
return (_Recordset->Fields->Item[fieldname]->Value).operator float();
}
}
return ret;
}
BOOL CAdoRecordset::GetFieldValueBool( const int fieldorder )
{
BOOL ret = FALSE;
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
int fieldCount = _Recordset->GetFields()->GetCount();
if( fieldCount > 0 ) {
if( fieldorder >= 0 && fieldorder < fieldCount ) {
ret = (BOOL)((_Recordset->GetFields()->Item[fieldorder]->Value).operator bool());
}
}
}
}
return ret;
}
BOOL CAdoRecordset::GetFieldValueBool( const TCHAR *fieldname )
{
BOOL ret = FALSE;
if( IsOpened() ) {
if( NULL != _Recordset->GetFields() ) {
return (BOOL)((_Recordset->Fields->Item[fieldname]->Value).operator bool());
}
}
return ret;
}
使用：
if (!AfxOleInit())
{
AfxMessageBox(IDP_OLE_INIT_FAILED);
return FALSE;
}
if( NULL == CAdoConnection::GetAdoConnection() ) {
g_Log.Write( _T("連線資料庫失敗") );
return -1;
}
// ......
CString strCmd;
strCmd.Format( _T("SELECT * FROM StdTable WHERE (Id='%d')"), m_Id );
try {
CAdoConnection *pAdoConn = CAdoConnection::GetAdoConnection();
CAdoRecordset recordset;
pAdoConn->OpenRecordset( strCmd.GetBuffer(0), recordset );
int count = recordset.GetRecordCount();
if( count > 0 ) {
_count = count;
_list = new MyList[count];
recordset.MoveFirst();
for( int i = 0; i < count; i++ ) {
_list[i].SetId( recordset.GetFieldValueInt(_T("Id")) );
_list[i].SetName( recordset.GetFieldValueStr(_T("Name")) );
recordset.MoveNext();
}
}
}
catch( _com_error e ) {
CString strError;
strError.Format( _T("Error: %s\r\n"), e.ErrorMessage() );
AfxMessageBox( strError );
}
// ......
CAdoConnection *pAdoConn = CAdoConnection::GetAdoConnection();
if( NULL == pAdoConn )
return FALSE;
CString strSql;
strSql.Format( _T("INSERT INTO StdTable(Name, Id) VALUES('%s', '%d')"), m_Name, _Id );
if( !pAdoConn->ExecuteNonQuery(strSql.GetBuffer(0)) )
return FALSE;
// ......
CAdoConnection::DestroyAdoConnection();
AfxOleTerm(FALSE);