Question

I have to read data from mdb-files using c++ but I’m having trouble getting started. I found this tutorial, but my code always crashes when I try to connect to a local database file.

ADO::_ConnectionPtr conn;
conn.CreateInstance( __uuidof( ADO::Connection ) ); 
conn->Open( L"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\database.mdb;", 
                        L"", 
                        L"password", 
                        ADO::adConnectUnspecified);

Is there anything wrong with the code above?

Answer 1

If you add some error handling, it won’t crash. and you’ll have a chance of diagnosing what’s going wrong:

try {
    ADO::_ConnectionPtr conn;
    conn.CreateInstance( __uuidof( ADO::Connection ) );
    conn->Open( L"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\database.mdb;",
        L"",
        L"password",
        ADO::adConnectUnspecified);
} 

catch (_com_error& e) {
    printf("Error:\n");
    printf("Code = %08lx\n", e.Error());
    printf("Message = %s\n", e.ErrorMessage());
    printf("Source = %s\n", (LPCSTR) e.Source());
    printf("Description = %s\n", (LPCSTR) e.Description());
}