Type, exemple de propriété (objet Property) (VC++)

Cet exemple illustre la propriété Type. Il s’agit d’un modèle d’utilitaire pour répertorier les noms et les types d’une collection, comme Properties, Fields, etc.

Nous n’avons pas besoin d’ouvrir l’objet Recordset pour accéder à sa collection Properties ; les propriétés apparaissent lorsque l’objet Recordset est instancié. Toutefois, la définition de la propriété CursorLocation sur adUseClient ajoute plusieurs propriétés dynamiques à la collection Properties de l’objet Recordset, ce qui rend l’exemple un peu plus intéressant. Par souci d’illustration, nous utilisons explicitement la propriété Item pour accéder à chaque objet Property.

// BeginTypePropertyCpp.cpp  
// compile with: /EHsc  
#import "msado15.dll" no_namespace rename("EOF", "EndOfFile")  
  
// Function declarations  
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);};  
void TypeX();  
void PrintComError(_com_error &e);  
  
int main() {  
   if (FAILED(::CoInitialize(NULL)))  
      return -1;  
  
   TypeX();  
   ::CoUninitialize();  
}  
  
void TypeX() {  
   // Define ADO object pointers, initialize pointers. These are in the ADODB:: namespace  
   _RecordsetPtr pRst = NULL;  
   PropertyPtr pProperty = NULL;  
  
   // Define Other Variables  
   _bstr_t strMsg;  
   _variant_t vIndex;  
   int intLineCnt = 0;     
  
   try {  
      TESTHR(pRst.CreateInstance (__uuidof(Recordset)));  
  
      // Set the Recordset Cursor Location  
      pRst->CursorLocation = adUseClient;  
  
      for (short iIndex = 0; iIndex <= (pRst->Properties->GetCount() - 1);iIndex++) {  
         vIndex = iIndex;  
         pProperty = pRst->Properties->GetItem(vIndex);  
  
         int propType = (int)pProperty->GetType();  
  
         switch(propType) {  
         case adBigInt:  
            strMsg = "adBigInt";  
            break;  
         case adBinary:  
            strMsg = "adBinary";  
            break;  
         case adBoolean:  
            strMsg = "adBoolean";  
            break;  
         case adBSTR:  
            strMsg = "adBSTR";  
            break;  
         case adChapter:  
            strMsg = "adChapter";  
            break;  
         case adChar:  
            strMsg = "adChar";  
            break;  
         case adCurrency:  
            strMsg = "adCurrency";  
            break;  
         case adDate:  
            strMsg = "adDate";  
            break;  
         case adDBDate:  
            strMsg = "adDBDate";  
            break;  
         case adDBTime:  
            strMsg = "adDBTime";  
            break;  
         case adDBTimeStamp:  
            strMsg = "adDBTimeStamp";  
            break;  
         case adDecimal:  
            strMsg = "adDecimal";  
            break;  
         case adDouble:  
            strMsg = "adDouble";  
            break;  
         case adEmpty:  
            strMsg = "adEmpty";  
            break;  
         case adError:  
            strMsg = "adError";  
            break;  
         case adFileTime:  
            strMsg = "adFileTime";  
            break;  
         case adGUID:  
            strMsg = "adGUID";  
            break;  
         case adIDispatch:  
            strMsg = "adIDispatch";  
            break;  
         case adInteger:  
            strMsg = "adInteger";  
            break;  
         case adIUnknown:  
            strMsg = "adIUnknown";  
            break;  
         case adLongVarBinary:  
            strMsg = "adLongVarBinary";  
            break;  
         case adLongVarChar:  
            strMsg = "adLongVarChar";  
            break;  
         case adLongVarWChar:  
            strMsg = "adLongVarWChar";  
            break;  
         case adNumeric:  
            strMsg = "adNumeric";  
            break;  
         case adPropVariant:  
            strMsg = "adPropVariant";  
            break;  
         case adSingle:  
            strMsg = "adSingle";  
            break;  
         case adSmallInt:  
            strMsg = "adSmallInt";  
            break;  
         case adTinyInt:  
            strMsg = "adTinyInt";  
            break;  
         case adUnsignedBigInt:  
            strMsg = "adUnsignedBigInt";  
            break;  
         case adUnsignedInt:  
            strMsg = "adUnsignedInt";  
            break;  
         case adUnsignedSmallInt:  
            strMsg = "adUnsignedSmallInt";  
            break;  
         case adUnsignedTinyInt:  
            strMsg = "adUnsignedTinyInt";  
            break;  
         case adUserDefined:  
            strMsg = "adUserDefined";  
            break;  
         case adVarBinary:  
            strMsg = "adVarBinary";  
            break;  
         case adVarChar:  
            strMsg = "adVarChar";  
            break;  
         case adVariant:  
            strMsg = "adVariant";  
            break;  
         case adVarNumeric:  
            strMsg = "adVarNumeric";  
            break;  
         case adVarWChar:  
            strMsg = "adVarWChar";  
            break;  
         case adWChar:  
            strMsg = "adWChar";  
            break;  
         default:  
            strMsg = "*UNKNOWN*";  
            break;  
         }  
  
         intLineCnt++;  
  
         printf ("Property %d : %s,Type = %s\n",iIndex, (LPCSTR)pProperty->GetName(),  
            (LPCSTR)strMsg);  
      }  
   }  
   catch(_com_error &e) {  
      // Notify the user of errors if any.  
      PrintComError(e);  
   }  
}  
  
void PrintComError(_com_error &e) {  
  
   _bstr_t bstrSource(e.Source());  
   _bstr_t bstrDescription(e.Description());  
  
   // Print Com errors.    
   printf("Error\n");  
   printf("\tCode = %08lx\n", e.Error());  
   printf("\tCode meaning = %s\n", e.ErrorMessage());  
   printf("\tSource = %s\n", (LPCSTR) bstrSource);  
   printf("\tDescription = %s\n", (LPCSTR) bstrDescription);  
}  

Voir aussi

Property, objet (ADO)
Type, propriété (ADO)