ActiveConnection-Eigenschaft (Catalog) (VC++-Beispiel)

Gilt für: Access 2013, Office 2013

Durch das Festlegen der ActiveConnection-Einstellung auf eine gültige, offene Verbindung wird der Katalog geöffnet. Über einen geöffneten Katalog können Sie auf die Schemaobjekte zugreifen, die in dem jeweiligen Katalog enthalten sind.

 
// BeginActiveConnectionCpp 
#import "c:\Program Files\Common Files\system\ado\msado15.dll" 
#import "c:\Program Files\Common Files\system\ado\msadox.dll" no_namespace 
 
#include "iostream.h" 
#include "stdio.h" 
#include "conio.h" 
 
// Function declarations 
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);}; 
void OpenConnectionX(void); 
void OpenConnectionWithStringX(void); 
 
////////////////////////////////////////////////////////// 
// // 
// Main Function // 
// // 
////////////////////////////////////////////////////////// 
void main() 
{ 
 if(FAILED(::CoInitialize(NULL))) 
 return; 
 
 OpenConnectionX(); 
 
 OpenConnectionWithStringX(); 
 
 ::CoUninitialize(); 
} 
 
////////////////////////////////////////////////////////// 
// // 
// OpenConnectionX Function // 
// // 
////////////////////////////////////////////////////////// 
void OpenConnectionX(void) 
{ 
 HRESULT hr = S_OK; 
 
 // Define ADOX object pointers. 
 // Initialize pointers on define. 
 // These are in the ADOX:: namespace. 
 _CatalogPtr m_pCatalog = NULL; 
 
 //Define ADODB object pointers 
 ADODB::_ConnectionPtr m_pCnn = NULL; 
 
 // Define string variables. 
 _bstr_t strcnn("Provider='Microsoft.JET.OLEDB.4.0';" 
 "Data source = 'c:\\Program Files\\Microsoft Office\\" 
 "Office\\Samples\\Northwind.mdb';"); 
 
 try 
 { 
 TESTHR(hr = m_pCnn.CreateInstance(__uuidof(ADODB::Connection))); 
 TESTHR(hr = m_pCatalog.CreateInstance(__uuidof (Catalog))); 
 m_pCnn->Open(strcnn,"","",NULL); 
 m_pCatalog->PutActiveConnection(_variant_t((IDispatch *) m_pCnn)); 
 _variant_t vIndex = (short) 0; 
 cout<<m_pCatalog->Tables->GetItem(vIndex)->Type<<endl; 
 } 
 catch(_com_error &e) 
 { 
 // Notify the user of errors if any. 
 _bstr_t bstrSource(e.Source()); 
 _bstr_t bstrDescription(e.Description()); 
 
 printf("\n\tSource : %s \n\tdescription : %s \n ", 
 (LPCSTR)bstrSource,(LPCSTR)bstrDescription); 
 } 
 catch(...) 
 { 
 cout << "Error occured in OpenConnectionX...."<< endl; 
 } 
 
 if (m_pCnn) 
 if (m_pCnn->State == 1) 
 m_pCnn->Close(); 
} 
 
////////////////////////////////////////////////////////// 
// // 
// OpenConnectionWithStringX Function // 
// // 
////////////////////////////////////////////////////////// 
void OpenConnectionWithStringX(void) 
{ 
 HRESULT hr = S_OK; 
 
 // Define ADOX object pointers. 
 // Initialize pointers on define. 
 // These are in the ADOX:: namespace. 
 _CatalogPtr m_pCatalog = NULL; 
 
 // Define string variables. 
 _bstr_t strcnn("Provider='Microsoft.JET.OLEDB.4.0';" 
 "Data source = 'c:\\Program Files\\Microsoft Office\\" 
 "Office\\Samples\\Northwind.mdb';"); 
 
 try 
 { 
 TESTHR(hr = m_pCatalog.CreateInstance(__uuidof (Catalog))); 
 m_pCatalog->PutActiveConnection(strcnn); 
 _variant_t vIndex = (short) 0; 
 cout<<m_pCatalog->Tables->GetItem(vIndex)->Type<<endl; 
 } 
 catch(_com_error &e) 
 { 
 // Notify the user of errors if any. 
 _bstr_t bstrSource(e.Source()); 
 _bstr_t bstrDescription(e.Description()); 
 
 printf("\n\tSource : %s \n\tdescription : %s \n ", 
 (LPCSTR)bstrSource,(LPCSTR)bstrDescription); 
 } 
 catch(...) 
 { 
 cout << "Error occured in OpenConnectionWithStringX...."<< endl; 
 } 
} 
// EndActiveConnectionCpp