Menggunakan Antarmuka COM

Kode klien adalah pengguna antarmuka COM. Untuk menggunakan antarmuka COM, kustom atau standar apa pun, klien harus mengetahui IID-nya. Dalam contoh berikut, driver yang memanggil CustomRpt meneruskannya dengan nama objek yang dikonversi ke format karakter lebar. Nama objek diumpankan ke CreateFileMoniker sehingga moniker file dapat dibuat dan klien dapat mengikat ke objek yang sedang berjalan. Setelah objek berjalan, CustomRpt dapat mengakses penunjuk ke antarmuka di proksi/stub standar, seperti IPersistFile, atau ke antarmuka kustom, ICustomInterface.

void CustomRpt(char *pszObject) 
{ 
    HRESULT             hr; 
    WCHAR               wszObject[128]; 
    WCHAR               wszMsg[128] = {L"Your Message Here...\n"}; 
    IMoniker            *pmkObject = NULL; 
    IUnknown            *pIUnk = NULL; 
    IPersistFile        *pIPersistFile = NULL; 
    ICustomInterface    *pICustomInterface = NULL; 
 
    // Create a wide-character version of the object's file name. 
    StringCchPrintf(wszObject, 128, L"%hs", pszObject); 
 
    // Get a file moniker for the object (a *.smp file). 
    hr = CreateFileMoniker(wszObject, &pmkObject); 
 
    if(FAILED(hr)) 
    { 
        printf("Client: CreateFileMoniker for Object failed"); 
        return; 
    } 
 
    // BindMoniker is equivalent to calling CreateBindCtx() followed by 
    // a call to BindToObject(). It has the net result of binding the 
    // interface (specified by the IID) to the moniker. 
 
    hr = BindMoniker(pmkObject, 0, IID_IUnknown, (void **)&pIUnk); 
    if (FAILED(hr)) 
    { 
        printf("Client: BindMoniker failed (%x)\n", hr); 
        return; 
    } 
 
    // Try a couple QueryInterface calls into the object code; first a 
    // QueryInterface to IPersistFile... 
 
    hr = pIUnk->QueryInterface(IID_IPersistFile, (void **)&pIPersistFile); 
 
    if (FAILED(hr)) { 
        printf("Client: QueryInterface IPersistFile failed (%x)\n", hr); 
        pIUnk->Release(); 
        return; 
    } 
 
    // Followed by a QueryInterface to ICustomInterface. 
    hr = pIUnk->QueryInterface(IID_ICustomInterface, (void **)&pICustomInterface); 
 
    if (FAILED(hr)) { 
        printf("Client: QueryInterface failed (%x)\n", hr); 
        pIUnk->Release(); 
        pIPersistFile->Release(); 
        return; 
    } 
 
    // CustomReport() is the object function that displays the time and 
    // date information on the object. 
    hr = pICustomInterface->CustomReport(); 
 
    if (FAILED(hr)) 
    { 
        printf("Client: pICustomInterface->CustomReport failed (%x)\n", hr); 
        pIUnk->Release(); 
        pIPersistFile->Release(); 
        return; 
    } 
 
    // Clean up resources by calling release on each of the interfaces. 
    pIPersistFile->Release(); 
    pICustomInterface->Release(); 
    pIUnk->Release(); 
    return; 
}