ParentCatalog Property Example (VC++)

Microsoft ActiveX Data Objects (ADO)

ADOX 2.5

ParentCatalog Property Example (VC++)

The following code demonstrates how to use the ParentCatalog property to access a provider-specific property prior to appending a table to a catalog. The property is AutoIncrement, which creates an AutoIncrement field in a Microsoft Jet database.

// BeginCreateAutoIncrColumnCpp
#import "c:\Program Files\Common Files\system\ado\msadox.dll" \
    no_namespace
#import "c:\Program Files\Common Files\system\ado\msado15.dll"

#include "iostream.h"
#include "stdio.h"
#include "conio.h"

//Function declarations
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);};
void CreateAutoIncrColumnX(void);

//////////////////////////////////////////////////////////
//                                                      //
//      Main Function                                   //
//                                                      //
//////////////////////////////////////////////////////////
void main()
{
    if(FAILED(::CoInitialize(NULL)))
        return;

    CreateAutoIncrColumnX();

     ::CoUninitialize();
}

//////////////////////////////////////////////////////////
//                                                      //
//       CreateAutoIncrColumnX Function                 //
//                                                      //
//////////////////////////////////////////////////////////
void CreateAutoIncrColumnX(void)
{
    HRESULT hr = S_OK;

    // Define ADOX object pointers.
    // Initialize pointers on define.
    // These are in the ADOX::  namespace.
    _CatalogPtr m_pCatalog = NULL;
    _TablePtr m_pTable = 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)));
        
        TESTHR(hr = m_pTable.CreateInstance(__uuidof (Table)));

        // Connect the catalog.
        m_pCnn->Open (strCnn, "", "", NULL);

        m_pCatalog->PutActiveConnection(variant_t((IDispatch *)m_pCnn));

        m_pTable->Name="MyContacts";
        m_pTable->ParentCatalog = m_pCatalog;

        // Create fields and append them to the new Table object.
        m_pTable->Columns->Append("ContactId", adInteger,0);

        // Make the ContactId column and auto incrementing column
        m_pTable->Columns->GetItem("ContactId")->Properties->
            GetItem("AutoIncrement")->Value = true;
        m_pTable->Columns->Append("CustomerID", adVarWChar,0);
        m_pTable->Columns->Append("FirstName", adVarWChar,0);
        m_pTable->Columns->Append("LastName", adVarWChar,0);
        m_pTable->Columns->Append("Phone", adVarWChar, 20);
        m_pTable->Columns->Append("Notes", adLongVarWChar,0);
        m_pCatalog->Tables->Append(_variant_t((IDispatch*)m_pTable));

        // Refresh the database.
        m_pCatalog->Tables->Refresh();

        printf("Table 'MyContacts' is added.\n");

        // Delete new table, since this is only an example
        m_pCatalog->Tables->Delete("MyContacts");

        printf("Table 'MyContacts' is deleted.\n");
    }
    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 CreateAutoIncrColumnX...."<< endl;
    }

    m_pCatalog = NULL;
}
// EndCreateAutoIncrColumnCpp

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