Ejemplo de propiedades Description, HelpContext, HelpFile, NativeError, Number, Source y SQLState (VC++)

En este ejemplo se desencadena un error, se intercepta y se muestran las Description, HelpContext, HelpFile, NativeError, Number, Sourcey SQLState propiedades del objeto Error resultante.

// BeginDescriptionCpp.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 DescriptionX();  
void PrintProviderError(_ConnectionPtr pConnection);  
void PrintComError(_com_error &e);  
  
int main() {  
   if (FAILED(::CoInitialize(NULL)))  
      return -1;  
  
   DescriptionX();  
   ::CoUninitialize();  
}  
  
void DescriptionX() {  
   // Define ADO object pointers. Initialize pointers on define. These are in the ADODB::  namespace  
   _ConnectionPtr pConnection = NULL;  
   ErrorPtr errorLoop = NULL;  
  
   // Define Other Variables  
   HRESULT hr = S_OK;  
  
   try {  
      // Intentionally trigger an error.  open connection  
      TESTHR(pConnection.CreateInstance(__uuidof(Connection)));  
  
      if (FAILED(hr = pConnection->Open("Nothing", "", "", adConnectUnspecified))) {  
         _com_issue_error(hr);  
         exit(1);  
      }  
  
      // Cleanup object before exit.  
      pConnection->Close();  
   }  
   catch(_com_error) {  
      // Pass a connection pointer.  
      PrintProviderError(pConnection);  
   }  
}  
  
void PrintProviderError(_ConnectionPtr pConnection) {  
   // Define Other Variables  
   HRESULT hr = S_OK;  
   _bstr_t strError;  
   ErrorPtr pErr = NULL;  
  
   try {  
      // Enumerate Errors collection and display properties of each Error object.  
      long nCount = pConnection->Errors->Count;  
  
      // Collection ranges from 0 to nCount - 1.  
      for ( long i = 0 ; i < nCount ; i++ ) {  
         pErr = pConnection->Errors->GetItem(i);  
         printf("Error #%d\n", pErr->Number);  
         printf(" %s\n", (LPCSTR)pErr->Description);  
         printf(" (Source: %s)\n", (LPCSTR)pErr->Source);  
         printf(" (SQL State: %s)\n", (LPCSTR)pErr->SQLState);  
         printf(" (NativeError: %d)\n", (LPCSTR)pErr->NativeError);  
  
         if ((LPCSTR)pErr->GetHelpFile() == NULL)  
            printf("\tNo Help file available\n");  
         else {  
            printf("\t(HelpFile: %s\n)" ,pErr->HelpFile);  
            printf("\t(HelpContext: %s\n)" , pErr->HelpContext);  
         }  
      }  
   }  
  
   catch(_com_error &e) {  
      // Notify the user of errors if any.  
      PrintComError(e);  
   }  
}  
  
void PrintComError(_com_error &e) {  
   // Notify the user of errors if any.  
   _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", e.ErrorMessage());  
   printf("\tSource = %s\n", (LPCSTR) bstrSource);  
   printf("\tDescription = %s\n", (LPCSTR) bstrDescription);  
}  

Consulte también

de propiedades Description
del objeto Error de
HelpContext, propiedades HelpFile
HelpContext, propiedades HelpFile
propiedad NativeError (ADO)
propiedad number (ADO) de
propiedad source (error de ADO)
de la propiedad SQLState