Windows Media Player 11 SDK Retrieving the Burn Status 

Retrieving the Burn Status

In the code example that follows, the following dialog controls are defined:

You can monitor the progress of the burning operation by periodically calling IWMPCdromBurn::get_burnProgress while the CD is being burned. This method retrieves a progress value for the entire burning operation. The value retrieved is a number that represents the percentage of burning completed, from 0 to 100.

// Update the progress bar IDC_PROGRESS
// and the corresponding text string IDC_PROGRESS_TEXT.
long lProgress = 0;
hr = m_spCdromBurn->get_burnProgress(&lProgress);
if (SUCCEEDED(hr))
{
    SendMessage(GetDlgItem(IDC_PROGRESS),
        PBM_SETPOS, lProgress, 0);
    SetDlgItemInt(IDC_PROGRESS_TEXT, lProgress);
}

You can get the current state of the burning operation by calling IWMPCdromBurn::get_burnState. This method retrieves an enumeration specifying the current operation being performed.

// Retrieve the burn state.
WMPBurnState wmpbs = wmpbsUnknown;
HRESULT hr = m_spCdromBurn->get_burnState(&wmpbs);

if (SUCCEEDED(hr))
{
    // Set the burn state string.
    CComBSTR bstrState;
    switch (wmpbs)
    {
        case wmpbsUnknown:
        default:
            hr = bstrState.Append("Unknown state.");
            break;
        case wmpbsBusy:
            hr = bstrState.Append("Windows Media Player is Busy.");
            break;
        case wmpbsReady:
            hr = bstrState.Append("Ready to begin burning.");
            break;
        case wmpbsWaitingForDisc:
            hr = bstrState.Append("Waiting for disc.");
            break;
        case wmpbsRefreshStatusPending:
            hr = bstrState.Append("The burn playlist has changed.");
            m_spCdromBurn->refreshStatus();
            break;
        case wmpbsPreparingToBurn:
            hr = bstrState.Append("Preparing to burn the CD.");
            break;
        case wmpbsBurning:
            hr = bstrState.Append("The CD is being burned.");
            break;
        case wmpbsStopped:
            hr = bstrState.Append("The burning operation is stopped.");
            break;
        case wmpbsErasing:
            hr = bstrState.Append("Erasing the CD.");
            break;
    }
    if (SUCCEEDED(hr))
    {
        SetDlgItemTextW(IDC_BURN_STATE, bstrState.m_str);
    }
}

To retrieve the number of seconds of audio the CD can hold, call IWMPCdromBurn::getItemInfo with "AvailableTime" as the first parameter. The value retrieved by this function is represented by a string.

// Set "AvailableTime" string
CComBSTR bstrTime;
CComBSTR bstrItem;
HRESULT hr = bstrItem.Append("AvailableTime");
if (SUCCEEDED(hr))
{
    hr = m_spCdromBurn->getItemInfo(bstrItem, &bstrTime);
}
if (SUCCEEDED(hr))
{
    hr = bstrTime.Append(" seconds");
}
if (SUCCEEDED(hr))
{
    SetDlgItemTextW(IDC_AVAILABLE_TIME, bstrTime.m_str);
}

To retrieve the amount of free space on a disc, call IWMPCdromBurn::getItemInfo with "FreeSpace" as the first parameter. The value retrieved by this function is a string that represents the number of free bytes available on the disc.

// Set "FreeSpace" string
CComBSTR bstrFreeSpace;
CComBSTR bstrItem;
HRESULT hr = bstrItem.Append("FreeSpace");
if (SUCCEEDED(hr))
{
    hr = m_spCdromBurn->getItemInfo(bstrItem, &bstrFreeSpace);
}
if (SUCCEEDED(hr))
{
    hr = bstrFreeSpace.Append(" bytes");
}
if (SUCCEEDED(hr))
{
    SetDlgItemTextW(IDC_FREE_SPACE, bstrFreeSpace.m_str);
}

To retrieve the total capacity of a disc, call IWMPCdromBurn::getItemInfo with "TotalSpace" as the first parameter. The value retrieved by this function is a string that corresponds to the total number of bytes on the disc.

// Set "TotalSpace" string.
CComBSTR bstrTotalSpace;
CComBSTR bstrItem;
HRESULT hr = bstrItem.Append("TotalSpace");
if (SUCCEEDED(hr))
{
    hr = m_spCdromBurn->getItemInfo(bstrItem, &bstrTotalSpace);
}
if (SUCCEEDED(hr))
{
    hr = bstrTotalSpace.Append(" bytes");
}
if (SUCCEEDED(hr))
{
    SetDlgItemTextW(IDC_TOTAL_SPACE, bstrTotalSpace.m_str);
}

See Also

• Burning a CD
• Retrieving the CD Burning Interface
• Starting the Burn Process
• Erasing a Rewritable CD
• Retrieving the Drive and Disc Status