WM_RENDERFORMAT
uFmt = (UINT) wParam; /* clipboard data format */
The WM_RENDERFORMAT message is sent to the clipboard owner when a particular format with delayed rendering needs to be rendered. The receiver should render the data in that format and pass it to the clipboard by calling the SetClipboardData function.
uFmt
Specifies the data format. It can be any one of the formats described with the SetClipboardData function.
An application should return zero if it processes this message.
The application should not call the OpenClipboard and CloseClipboard functions while processing this message.
This example uses an application-defined function to render clipboard data. The function returns a data handle that is passed to the clipboard by the SetClipboardData function.
HANDLE hData;
case WM_RENDERFORMAT:
if (hData = RenderFormat(wParam))
SetClipboardData(wParam, hData);
break;
CloseClipboard, OpenClipboard, SetClipboardData, WM_RENDERALLFORMATS