程序代码：

#include "iostream.h"
#include "stdio.h"
#include "afx.h"
#include "icrsint.h"

#import "C:\Program Files\Common Files\System\ado\msado15.dll" \
    no_namespace rename("EOF", "adoEOF")

void TESTHR(HRESULT x) 
{if FAILED(x) _com_issue_error(x);} 

void PrintError(const char *cs)
{FILE *fd;
fd=fopen("log\\ADOError.log","ab+");
fprintf(fd,"%s%c%c",cs,13,10);
fclose(fd);
}


VOID PrintProviderError(_ConnectionPtr pConnection)
{
    ErrorPtr  pErr = NULL;
    long      nCount = 0;    
    long      i = 0;

    if( (pConnection->Errors->Count) > 0)
    {
        nCount = pConnection->Errors->Count;
        for(i = 0; i < nCount; i++)
        {
            pErr = pConnection->Errors->GetItem(i);
            PrintError((LPCSTR)pErr->Description);
        }
    }
}

void  AddNewX(void)
{
    // Define ADO object pointers.
    // Initialize pointers on define.
    _RecordsetPtr  pRecords = NULL;
    _ConnectionPtr pConnection   = NULL;

    //Define Other variables
    IADORecordBinding   *picRs = NULL;  //Interface Pointer declared.
    //CEmployeeRs emprs;                  //C++ class object   
    HRESULT hr = S_OK;

    
    _bstr_t strCnn("Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=weather_normal;");
    
  

    try
    {
        //Open a connection
        strCnn=("Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=weather_normal;");
        TESTHR(pConnection.CreateInstance(__uuidof(Connection)));
        hr = pConnection->Open(strCnn,"","",NULL);

        //_RecordsetPtr pRecords;
        
    
        TESTHR(pRecords.CreateInstance(__uuidof(Recordset)));
        hr=pRecords->Open("select weather,feel,temperature,wind,result from tab_weather ",
                          _variant_t((IDispatch *) pConnection, true),adOpenKeyset,adLockOptimistic,adCmdText);
        TESTHR(hr);    
        
        
        _bstr_t   sql;

        _variant_t vweather; //变量声明

        CString strusername;
        sql="select weather,feel,temperature,wind,result from tab_weather"; 
        pRecords=pConnection->Execute(sql,NULL,adCmdText);
        while(!pRecords->adoEOF)
        {
            vweather = pRecords->GetCollect("weather");///取得weather字段的值
            strusername = (TCHAR*)(_bstr_t)vweather ;//转换为字符串
            printf("%s\n",strusername);
            
            pRecords->MoveNext();///移到下一条记录
        }


    
        

        if (picRs)
            picRs->Release();

        pRecords->Close();
        pConnection->Close();

    }
    
    catch(_com_error &e)
    {
        // Notify the user of errors if any.
        _variant_t vtConnect = pRecords->GetActiveConnection();
        
    }
        
}

//==========================================
//==========================================
//==========================================
void main()
{
    if(FAILED(::CoInitialize(NULL))) 
        return; 

    AddNewX();

    ::CoUninitialize();
}