利用ADO引擎方式访问Oracle数据库的实现方法: 定义数据库头文件为CDBOperation.h #pragma once #import C:\Program Files\Com
利用ADO引擎方式访问Oracle数据库的实现方法:
定义数据库头文件为CDBOperation.h
#pragma once
#import "C:\Program Files\Common Files\System\ADO\msado15.dll" no_namespace rename("EOF","adoEOF"),rename("LockTypeEnum","AdoLockTypeEnum"),rename("DataTypeEnum","AdoDataTypeEnum"),\
rename("FieldAttributeEnum","AdoFieldAttributeEnum"),rename("EditModeEnum","AdoEditModeEnum"),rename("RecordStatusEnum","AdoRecordStatusEnum"),rename("ParameterDirectionEnum","AdoParameterDirectionEnum")
class CDBOperation
{
public:
//初始化数据库操作需要的对象
CDBOperation(void);
~CDBOperation(void);
//连接至数据库
bool ConnToDB();
//数据库操作函数
//查询操作 删除以及添加
_RecordsetPtr ExecuteWithResSQL(const char *);
private:
void PrintErrorInfo(_com_error &);
private:
//初始化数据库连接、命令、记录集
_ConnectionPtr CreateConnPtr();
_CommandPtr CreateCommPtr();
_RecordsetPtr CreateRecsetPtr();
private:
//数据库连接需要的连接、命令操作对象
_ConnectionPtr m_pConnection;
_CommandPtr m_pCommand;
};
定义程序源文件CDBOperation.cpp
#include "CDBOperation.h"
CDBOperation::CDBOperation(void)
{
CoInitialize(NULL);
m_pConnection = CreateConnPtr();
m_pCommand = CreateCommPtr();
}
CDBOperation::~CDBOperation(void)
{
m_pConnection->Close();
}
bool CDBOperation::ConnToDB()
{
if (NULL == m_pConnection)
{
printf("Failed to create connection\n");
return false;
}
try
{
_bstr_t strConnect="Provider=OraOLEDB.Oracle;User ID=scott;Password=19900624;Persist Security Info=True;Data Source=\"(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = 10.108.85.137)(PORT = 1521)) )(CONNECT_DATA = (SID = ORCL)(SERVER=DEDICATED)))\"";
HRESULT hr=m_pConnection->Open(strConnect,"","",NULL);
if (TRUE == FAILED(hr))
{
return false;
}
m_pCommand->ActiveConnection = m_pConnection;
return true;
}
catch(_com_error &e)
{
PrintErrorInfo(e);
return false;
}
}
_RecordsetPtr CDBOperation::ExecuteWithResSQL(const char *sql)
{
try
{
m_pCommand->CommandText = _bstr_t(sql);
_RecordsetPtr pRst = m_pCommand->Execute(NULL, NULL, adCmdText);
return pRst;
}
catch(_com_error &e)
{
PrintErrorInfo(e);
return NULL;
}
}
void CDBOperation::PrintErrorInfo(_com_error &e)
{
printf("Error infomation are as follows\n");
printf("ErrorNo: %d\nError Message:%s\nError Source:%s\nError Description:%s\n", e.Error(), e.ErrorMessage(), (LPCTSTR)e.Source(), (LPCTSTR)e.Description());
}
_ConnectionPtr CDBOperation::CreateConnPtr()
{
HRESULT hr;
_ConnectionPtr connPtr;
hr = connPtr.CreateInstance(__uuidof(Connection));
if (FAILED(hr) == TRUE)
{
return NULL;
}
return connPtr;
}
_CommandPtr CDBOperation::CreateCommPtr()
{
HRESULT hr;
_CommandPtr commPtr;
hr = commPtr.CreateInstance(__uuidof(Command));
if (FAILED(hr) == TRUE)
{
return NULL;
}
return commPtr;
}
_RecordsetPtr CDBOperation::CreateRecsetPtr()
{
HRESULT hr;
_RecordsetPtr recsetPtr;
hr = recsetPtr.CreateInstance(__uuidof(Recordset));
if (FAILED(hr) ==TRUE)
{
return NULL;
}
return recsetPtr;
}