This message is sent when the clipboard contains a data handle for the CF_OWNER-DISPLAY format (specifically the clipboard owner should display the clipboard contents)and the Clipboard application's client area needs repainting. The WM_PAINTCLIPBOARD message is sent to the clipboard owner to request repainting of all or part of the Clipboard application's client area.
| Parameter | Description |
| wParam | Contains a handle to the Clipboard-application window. | |
| lParam | The low-order word of the lParam parameter identifies a PAINTSTRUCT data structure that defines what part of the client area to paint. The high-order word is not used. |
To determine whether the entire client area or just a portion of it needs repainting, the clipboard owner must compare the dimensions of the drawing area given in the rcpaint field of the PAINTSTRUCT data structure to the dimensions given in the most recent WM_SIZECLIPBOARD message.
An application must use the GlobalLock function to lock the memory that contains the PAINTSTRUCT data structure. The application should unlock that memory by using the GlobalUnlock function before it yields or returns control.