C++ 连接Oracle

下面是一个ADO方式连接Oracle的小程序部分代码......

首先是Oracle的配置、在Oracle的安装路径下找到：Oracle\network\ADMIN\tnsnames.ora文件、配置一下连接配置

 

BOSS =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = xx.xx.xx.xx)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVICE_NAME = boss)
    )
  )

新建一个头文件、名为CDBOperation.h：

 

 

#pragma once
#import "c:\program files\common files\system\ado\msado15.dll" no_namespace rename("EOF", "adoEOF")
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(char *ConnectionString, char *UserID, char *Password);

    //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;
};

新建一个c++源文件、名为CDBOperation.cpp：

#include "stdafx.h"
#include "DBOperation.h"
CDBOperation::CDBOperation(void)
{
    CoInitialize(NULL);
    m_pConnection = CreateConnPtr();
    m_pCommand = CreateCommPtr();
}
CDBOperation::~CDBOperation(void)
{
    m_pConnection->Close();
}
bool CDBOperation::ConnToDB(char *ConnectionString, char *UserID, char *Password)
{
    if (NULL == m_pConnection)
    {
        printf("Failed to create connection\n");
        return false;
    }
    try
    {
        HRESULT hr = m_pConnection->Open(ConnectionString, UserID, Password, 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(Command));
    if (FAILED(hr) ==TRUE)
    {
        return NULL;
    }
    return recsetPtr;
}

我的代码是放在MFC一个按钮Click事件里面的：

 

记住在处理事件的cpp文件中导入头文件：#include "DBOperation.h"

 

CDBOperation dbOper;
    bool bConn = dbOper.ConnToDB("Provider=OraOLEDB.Oracle.1;Persist Security Info=True;Data Source=boss", "用户名", "密码");
    if (false == bConn)
    {
        MessageBox((LPCTSTR)"连接数据库出现错误\0",0,0);
        return;
    }

    //查询
    _RecordsetPtr pRst;
    char sql[255] = {0};
    strcpy(sql, " select * from boss_test_table2 where rownum = 1 ");
    pRst = dbOper.ExecuteWithResSQL(sql);
    if (NULL == pRst)
    {
        MessageBox(_T("查询数据出现错误！\0"),0,0);
        return;
    }
    if (pRst->adoEOF)
    {
        pRst->Close();
        MessageBox((LPCTSTR)"There is no records in this table\0",0,0);
        return;
    }
    _variant_t vSno, vName;
    while (!pRst->adoEOF)
    {
        //pRst->MoveFirst(); //记录集指针移动到查询结果集的前面
        vSno = pRst->GetCollect(_variant_t("U_NUMBER"));
        vName = pRst->GetCollect(_variant_t("USERS_NAME"));
        MessageBox((LPCTSTR)(_bstr_t)vSno,0,0);
        pRst->MoveNext();
    }

    strcpy(sql, "insert into boss_test_table2 (u_number, users_name, users_phone, status, customno_id) values ('0001', 'C+TTT+', '13999000000', 2, 'BPPPPPPPPPP')");
    pRst = dbOper.ExecuteWithResSQL(sql);
    if (NULL != pRst)
    {
        AfxMessageBox(_T("插入数据成功\n"));
    }
    //执行删除语句
    sprintf(sql, "delete boss_test_table2 where u_number = '%s'", "009");
    pRst = dbOper.ExecuteWithResSQL(sql);
    if (NULL != pRst)
    {
        MessageBox(_T("删除数据成功\0"),0,0);
    }
    //执行更新语句
    sprintf(sql, "update boss_test_table2 set users_name = '%s' ", "C++反人类、MFC反社会");
    pRst = dbOper.ExecuteWithResSQL(sql);
    if (NULL != pRst)
    {
        MessageBox(_T("更新数据成功\0"),0,0);
    }