INFO: SetClipboardData() and CF_PRIVATEFIRST (24252)
The information in this article applies to:
- Microsoft Platform Software Development Kit (SDK) 1.0
This article was previously published under Q24252 SUMMARY
The documentation for SetClipboardData() states that CF_PRIVATEFIRST can be
used to put private data formats on the clipboard. It also states that data
of this format is not automatically deleted. However, that is apparently
not true. That is, the data is removed automatically when the clipboard is
emptied (sending a WM_DESTROYCLIPBOARD message) and the new item is set
into the clipboard. The old item is shown; however, the handle now is
invalid because GlobalFree() is called on it.
MORE INFORMATION
GlobalFree() was not called on this handle. If you try to use the other
handle to this memory, you will find that the one you initially received
from GlobalAlloc() is still valid. Only the clipboard handle has been
invalidated by the call to EmptyClipboard().
The documentation states that "Data handles associated (with
CF_PRIVATEFIRST) will not be freed automatically." This statement refers to
the memory associated with that data handle. When SetClipboardData() is
called under standard data types, it frees the block of memory identified
by hMem. This is not the case for CF_PRIVATEFIRST. Applications that post
CF_PRIVATEFIRST items on the clipboard are responsible for the memory block
containing those items.
This is not intended to imply that items placed on the clipboard will
remain on the clipboard if they are CF_PRIVATEFIRST. When a call is made to
EmptyClipboard(), all objects will be removed.
| Modification Type: | Minor | Last Reviewed: | 7/11/2005 |
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| Keywords: | kbClipboard kbinfo KB24252 |
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