Version-Eigenschaft – Beispiel (VC++)
In diesem Beispiel wird die Version-Eigenschaft eines Connection-Objekts verwendet, um die aktuelle ADO-Version anzuzeigen. Außerdem werden mehrere dynamische Eigenschaften verwendet, um Folgendes anzuzeigen:
den aktuellen DBMS-Name und die aktuelle DBMS-Version.
die OLE DB-Version.
den Anbieternamen und die Anbieterversion.
die OLE DB-Version.
den ODBC-Treibername und die ODBC-Treiberversion.
Hinweis
Wenn Sie eine Verbindung mit einem Datenquellenanbieter herstellen, der Windows-Authentifizierung unterstützt, sollten Sie Trusted_Connection=yes oder Integrated Security=SSPI anstelle von Benutzer-ID- und Kennwortinformationen in der Verbindungszeichenfolge angeben.
// BeginVersionCpp.cpp
// compile with: /EHsc
#import "msado15.dll" no_namespace rename("EOF", "EndOfFile")
#include <ole2.h>
#include <stdio.h>
#include <conio.h>
// Function declarations
inline void TESTHR(HRESULT x) { if FAILED(x) _com_issue_error(x); };
void VersionX();
void PrintProviderError(_ConnectionPtr pConnection);
void PrintComError(_com_error &e);
int main() {
if (FAILED(::CoInitialize(NULL)))
return -1;
VersionX();
::CoUninitialize();
}
void VersionX() {
HRESULT hr = S_OK;
_bstr_t strCnn("Provider='sqloledb'; Data Source='My_Data_Source'; Initial Catalog='pubs'; Integrated Security='SSPI';");
// Define ADO object pointers. Initialize pointers on define.
// These are in the ADODB:: namespace.
_ConnectionPtr pConnection = NULL;
try {
// Open connection.
TESTHR(pConnection.CreateInstance(__uuidof(Connection)));
pConnection->Open (strCnn, "", "", adConnectUnspecified);
printf("ADO Version : %s\n\n",(LPCSTR) pConnection->Version);
printf("DBMS Name : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("DBMS Name")->Value);
printf("DBMS Version : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("DBMS Version")->Value);
printf("OLE DB Version : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("OLE DB Version")->Value);
printf("Provider Name : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("Provider Name")->Value);
printf("Provider Version : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("Provider Version")->Value);
printf("Driver Name : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("Driver Name")->Value);
printf("Driver Version : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("Driver Version")->Value);
printf("Driver ODBC Version : %s\n\n",(LPCSTR) (_bstr_t)
pConnection->Properties->GetItem("Driver ODBC Version")->Value);
}
catch (_com_error &e) {
// Notify the user of errors if any.
PrintProviderError(pConnection);
PrintComError(e);
}
if (pConnection)
if (pConnection->State == adStateOpen)
pConnection->Close();
}
void PrintProviderError(_ConnectionPtr pConnection) {
// Print Provider Errors from Connection object.
// pErr is a record object in the Connection's Error collection.
ErrorPtr pErr = NULL;
if ( (pConnection->Errors->Count) > 0) {
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 number: %x\t%s\n", pErr->Number, (LPCSTR) pErr->Description);
}
}
}
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);
}