ADO指针 _commandPtr 的用法

在VC++中使用_commandPtr 指针一个小例子中，用于备忘：

CString strSQL;

 strSQL = "select * from tb_hostlist";

_CommandPtr pCommamd;

_RecordsetPtr pRecord;

pCommamd.CreateInstance("ADODB.Command");

pRecord.CreateInstance("ADODB.Recordset");

try{

pCommamd->CommandText = _bstr_t(strSQL);

pCommamd->CommandType = adCmdText;

pCommamd->ActiveConnection = pConnection;

pRecord = pCommamd->Execute(NULL,NULL,adCmdText);

int icount;icount = pRecord->RecordCount;VARIANT vtValue;

while(!pRecord->AdoEOF)

{

vtValue = pRecord->GetCollect("mac") ;

m_list.AddString((vtValue.vt == VT_NULL) ?"null":(CHAR*)_bstr_t(vtValue));

pRecord->MoveNext();

}

 }catch(_com_error &e)

{

m_list.AddString(e.ErrorMessage());

}