VC连接Oracle数据库之ODBC及ADO

一.ODBC连ORACLE： 

str.Format( "Driver={Microsoft  ODBC  for  Oracle};Server=OracleServer.world;Uid=Username;Pwd=asdasd; ")
二.ADO连接ORACLE：

1.客户端一定要安装 Oracle的oledb的驱动。可到以下网址下载(10.版本的大概190M)

http://otn.oracle.com/software/tech/windows/ole_db/content.html

2.要使用Net Configuration Assistant配置好侦听及相关环境

代码

首先，在 stdafx.h 中加入以下代码，导入ado库

#import "c:\program files\common files\system\ado\msado15.dll" no_namespace rename ("EOF", "adoEOF")

其次，要确保有 ::CoInitialize(NULL)的调用，以初始化COM.

//类定义

class CDBOp  {public:    bool ReConnect();    bool CloseConnect();    bool OpenConnect(int dbType,  CString hostName,                     CString dBName, CString userName, CString password);    bool GetItemData(CString itemID, float &price, CString &descript);     //以上取存储过程数据，这里只是举例说明    CString GetErrorMsg();    CDBOp();    virtual ~CDBOp(); private:    _ConnectionPtr m_pConnection;  //连接对象    _RecordsetPtr m_pRecordset;     //记录集对象    bool   m_bConnectSuccess;     //连接是否成功    CString   m_strConnString;      //数据库连接字符串     CString   m_strErrMsg;           //保存错误信息};

//类实现

CDBOp::CDBOp():m_bConnectSuccess(false){    ::CoInitialize(NULL);    m_pConnection.CreateInstance("ADODB.Connection");    m_pConnection->ConnectionTimeout=30;     m_pRecordset.CreateInstance("ADODB.Recordset");}CDBOp::~CDBOp(){    //::CoUninitialize();    CloseConnect();}//打开连接(数据库类型，主机名，数据库名，登陆名，密码)//数据库类型: 0 为Sql server, 1为 Oraclebool CDBOp::OpenConnect(int dBType,          CString hostName,         CString dBName,         CString userName,         CString password)        {    CString strConn;     if (dBType =0)  //Sql server    {       strConn = "Provider=SQLOLEDB.1";       strConn+= ";User ID=";       strConn+= userName;       strConn+= ";Password=";       strConn+= password;       strConn+= ";Initial Catalog=";       strConn+= dBName;       strConn+= ";Data Source=";       strConn+= hostName;    }    else if (dBType =1) //Oracle    {      //MSDAORA or OraOLEDB.Oracle.1      strConn = "Provider=OraOLEDB.Oracle.1";      strConn+= ";Persist Security Info=true";      strConn+= ";User ID=";      strConn+= userName;      strConn+= ";Password=";      strConn+= password;      strConn+= ";Data Source=(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)";      strConn+= "(HOST=";      strConn+= hostName;      strConn+= ")(PORT=1521))(CONNECT_DATA=";      strConn+= "(SERVICE_NAME=";      strConn+= dBName;      strConn+= ")))";    }    if (strConn.IsEmpty())     {      m_strErrMsg="The connect string is null.";      return false;    }    CloseConnect();    m_strConnString =strConn;        return ReConnect();}//再次连接bool CDBOp::ReConnect(){    m_strErrMsg=_T("");    m_bConnectSuccess= false;    HRESULT hr;    try    {       hr = m_pConnection->Open(_bstr_t(m_strConnString), "", "", adModeUnknown);       if (SUCCEEDED(hr))       m_bConnectSuccess=true;      }    catch(_com_error e)    {         m_strErrMsg.Format("Connect database failure!\r\n\r\n message error:%s\r\n\r\n                           The connect string:%s",e.ErrorMessage(),m_strConnString);     }    return m_bConnectSuccess;}//关闭链接bool CDBOp::CloseConnect(){   if (m_bConnectSuccess)   {      if (m_pConnection->State==1)          m_pConnection->Close();       m_bConnectSuccess =false;   }   return true;}//取得错误信息CString CDBOp::GetErrorMsg(){   return m_strErrMsg;} bool CDBOp::GetItemData(CString itemID, float &price, CString &descript){    _CommandPtr   pCommand = NULL;    pCommand.CreateInstance("ADODB.Command");    #ifdef   _DEBUG       if   (pCommand   ==   NULL)       {         AfxMessageBox("Command Created fail! Please confirm whether initialize COM.");       }       #endif       ASSERT(pCommand   !=   NULL);      try       {           if (m_bConnectSuccess==false)       {           if (ReConnect()==false)            return false;        }     //输入参数   itemID         _ParameterPtr   pParamItemID;        pParamItemID.CreateInstance("ADODB.Parameter");        pParamItemID->Name="ItemID";   //所用存储过程参数名称        pParamItemID->Type=adChar;    //参数类型        pParamItemID->Size=10;     //参数大小        pParamItemID->Direction=adParamInput;  //表明是输入参数        pParamItemID->Value=_variant_t(itemID);        pCommand->Parameters->Append(pParamItemID);             //输出参数   price         _ParameterPtr   pParamPrice;            pParamPrice.CreateInstance("ADODB.Parameter");        pParamPrice->Name="Price";    //参数名称        pParamPrice->Type=adNumeric;    //参数类型        pParamPrice->Size=9;      //参数大小     pParamPrice->Precision =9;     pParamPrice->NumericScale =2;       pParamPrice->Direction=adParamOutput;  //声明是输出参数        pCommand->Parameters->Append(pParamPrice);        //输出参数   Descript         _ParameterPtr   pParamDescript;            pParamDescript.CreateInstance("ADODB.Parameter");        pParamDescript->Name="Descript";   //参数名称        pParamDescript->Type=adVarChar;    //参数类型        pParamDescript->Size=160;     //参数大小     pParamDescript->Direction=adParamOutput; //声明是输出参数        pCommand->Parameters->Append(pParamDescript);       //执行存储过程        pCommand->ActiveConnection=m_pConnection;        pCommand->CommandText="spItemInfo";   //存储过程名称        pCommand->CommandType=adCmdStoredProc;  //表示为存储过程adCmdStoredProc        pCommand->Execute(NULL,   NULL,   adCmdStoredProc);             price=(float)(pParamPrice->Value);     descript = (char*)_bstr_t(pParamDescript->Value);       return true;    }    catch(_com_error   e)       {               m_strErrMsg.Format(_T("Error:GetItemData. Reason:%s\n file: %s; line:                         %d\n"), e.ErrorMessage(), __FILE__, __LINE__);          return false;    }   }