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    • Adding clipboard support to a VC++ / MFC application is extremely simple. This article covers the basic steps involved in getting your applictions talking to the clipboard. In it are examples of the following:

    Reading and writing text

    The following source code demonstrates how to place text (contained in the CString "source") onto the clipboard. 

    CString source; 
//put your text in source

if(OpenClipboard())
{
	HGLOBAL clipbuffer;
	char * buffer;
	EmptyClipboard();
	clipbuffer = GlobalAlloc(GMEM_DDESHARE, source.GetLength()+1);
	buffer = (char*)GlobalLock(clipbuffer);
	strcpy(buffer, LPCSTR(source));
	GlobalUnlock(clipbuffer);
	SetClipboardData(CF_TEXT,clipbuffer);
	CloseClipboard();
}

    The source code below demonstrates the converse, how to retrieve text from the clipboard. 

    char * buffer = NULL;
//open the clipboard

CString fromClipboard;
if ( OpenClipboard() ) 
{
	HANDLE hData = GetClipboardData( CF_TEXT );
	char * buffer = (char*)GlobalLock( hData );
	fromClipboard = buffer;
	GlobalUnlock( hData );
	CloseClipboard();
}

    Reading and writing WMF (enhanced) data

    Writing and reading images to and from the clipboard can be very useful, and it is really very easy! The following example writes an enhanced metafile to the clipboard. 

    if ( OpenClipboard() )
{
	EmptyClipboard();

	//create the metafile DC

	CMetaFileDC * cDC = new CMetaFileDC();
	cDC->CreateEnhanced(GetDC(),NULL,NULL,"the_name");

	//call draw routine here that makes GDI calls int cDC


	//close meta CMetafileDC and get its handle

	HENHMETAFILE handle = cDC->CloseEnhanced();

	//place it on the clipboard

	SetClipboardData(CF_ENHMETAFILE,handle);
	CloseClipboard();

	//delete the dc

	delete cDC;
}

    Here is the converse. We get the metafile from the clipboard and draw it into our own client DC (just as a test, really you would want to make a copy). 

    if ( OpenClipboard() )
{
	//Get the clipboard data

	HENHMETAFILE handle = (HENHMETAFILE)GetClipboardData(CF_ENHMETAFILE);

	//play it into a DC (our own DC in this example)

	CClientDC dc(this);
	CRect client(0,0,200,200);
	dc.PlayMetaFile(handle,client);		

	//close the clipboard

	CloseClipboard();
}

    Reading and writing a bitmap

    Reading and writing a bitmap is only marginally trickier. The basic idea remains the same. Here is an example of saving a bitmap to the clipboard. 

    if ( OpenClipboard() )
{
	EmptyClipboard();
	//create some data

	CBitmap * junk = new CBitmap();
	CClientDC cdc(this);
	CDC dc;
	dc.CreateCompatibleDC(&cdc);
	CRect client(0,0,200,200);
	junk->CreateCompatibleBitmap(&cdc,client.Width(),client.Height());
	dc.SelectObject(junk);

	//call draw routine here that makes GDI calls

	DrawImage(&dc,CString("Bitmap"));

	//put the data on the clipboard

	SetClipboardData(CF_BITMAP,junk->m_hObject);
	CloseClipboard();

	//copy has been made on clipboard so we can delete

	delete junk;
}

    As with the other examples, here is an example of getting a bitmap from the clipboard. In this simple example we will just Blt it to the cleint DC. 

    if ( OpenClipboard() )
{

	//Get the clipboard data

	HBITMAP handle = (HBITMAP)GetClipboardData(CF_BITMAP);
	CBitmap * bm = CBitmap::FromHandle(handle);

	CClientDC cdc(this);
	CDC dc;
	dc.CreateCompatibleDC(&cdc);
	dc.SelectObject(bm);
	cdc.BitBlt(0,0,200,200,&dc,0,0,SRCCOPY);

	CloseClipboard();

}

    Setting up and using your own custom format

    By using the RegisterClipboardFormat() API you can copy and paste any type of data you want. This can be very useful in moving data between your own applications. Let's say we have a structure: 

    struct MyFormatData
{
	long val1;
	int val2;
};

    that we want to move on the clipboard. We can copy as follows: 

    UINT format = RegisterClipboardFormat("MY_CUSTOM_FORMAT");
if(OpenClipboard())
{
	//make some dummy data

	MyFormatData data;
	data.val1 = 100;
	data.val2 = 200;

	//allocate some global memory

	HGLOBAL clipbuffer;
	EmptyClipboard();
	clipbuffer = GlobalAlloc(GMEM_DDESHARE, sizeof(MyFormatData));
	MyFormatData * buffer = (MyFormatData*)GlobalLock(clipbuffer);

	//put the data into that memory

	*buffer = data;

	//Put it on the clipboard

	GlobalUnlock(clipbuffer);
	SetClipboardData(format,clipbuffer);
	CloseClipboard();
}

    To read it back off we do the inverse: 

    //second call with just get format already registered

UINT format = RegisterClipboardFormat("MY_CUSTOM_FORMAT");
MyFormatData data;
if ( OpenClipboard() ) 
{
	//get the buffer

	HANDLE hData = GetClipboardData(format);
	MyFormatData * buffer = (MyFormatData *)GlobalLock( hData );

	//make a local copy

	data = *buffer;

	GlobalUnlock( hData );
	CloseClipboard();
}

    Getting notified of clipboard changes

    It is very useful to be notified (via a windows message) whenever the clipboard has changed. To do this you use SetClipboardViewer() and then catch WM_DRAWCLIPBOARD 

    In your initialization code call:
	SetClipboardViewer();  //add us to clipboard change notification chain


In your message map add:
	ON_MESSAGE(WM_DRAWCLIPBOARD, OnClipChange)  //clipboard change notification


Which is declared as:
	afx_msg void OnClipChange();  //clipboard change notification


Finally implement:
void CDetectClipboardChangeDlg::OnClipChange() 
{
	//do something here, for example

	CTime time = CTime::GetCurrentTime();
	SetDlgItemText(IDC_CHANGED_DATE,time.Format("%a, %b %d, %Y -- %H:%M:%S"));

	DisplayClipboardText();
}

    Pasting data to another app's window

    One thing that I have found useful is to copy text to the clipboard (see above) and then to "paste" it to ANOTHER application!. I wrote a nice localization app that used a third party language translation package using this technique.

    Simply get the handle to the target window and send a "PASTE" to it. 

    	SendMessage(m_hTextWnd, WM_PASTE, 0, 0);
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     FirstPrevNext
    GeneralNEVER do this!!! Pin
    John Crenshaw    		14:05 12 Jun '09  
    Questioncompile error _UNICODE Pin
    winchnet2005    		15:33 16 Nov '08  
    AnswerRe: compile error _UNICODE Pin
    VEMS    		5:26 28 Jan '09  
    QuestionHow can manage all of copy and paste in system in C++ ->please help me Pin
    crackgns    		3:08 13 Aug '08  
    AnswerRe: How can manage all of copy and paste in system in C++ ->please help me Pin
    r1co    		20:21 17 Jan '09  
    QuestionHow to paste to a WORD app's window? Pin
    test_1550    		3:34 9 Sep '07  
    QuestionHow to get the XML data present in the Clipboard??? Pin
    gloriousgopi    		4:17 15 Feb '07  
    Generalhow to capture a big window? Pin
    Rockone    		3:42 8 Jan '07  
    GeneralClipboard Query. Pin
    Hakuna-Matada    		2:40 3 Aug '06  
    GeneralRe: Clipboard Query. Pin
    Ashutosh Bhawasinka    		9:40 12 Dec '06  
    GeneralRe: Clipboard Query. Pin
    Naadia    		21:14 27 Sep '07  
    Generalcrash with release edition Pin
    chinabcb163    		1:40 30 Jul '06  
    GeneralRe: crash with release edition Pin
    xox_c0bra_xox    		14:31 7 Sep '09  
    GeneralMemory Leak [modified] Pin
    Little.Ben    		2:31 26 Jul '06  
    QuestionRe: Memory Leak Pin
    PistolPeet    		8:01 9 May '07  
    AnswerRe: Memory Leak (it's not a leak) Pin
    dagronf    		18:11 27 Jun '07  
    GeneralRe: Memory Leak (it's not a leak) Pin
    PistolPeet    		0:19 28 Jun '07  
    GeneralHow OnPaintClipboard() do ? Pin
    trauconnguyen    		16:43 16 Apr '05  
    GeneralGetting a bitmap Pin
    tunerica    		19:45 22 Jul '04  
    GeneralPlease REJECT this article Pin
    Anonymous    		10:48 22 May '03  
    GeneralRe: Please REJECT this article Pin
    mathboy    		11:26 26 Jan '04  
    GeneralRe: Please REJECT this article Pin
    henky_arektc97    		20:00 11 May '06  
    GeneralRe: Please REJECT this article Pin
    xox_c0bra_xox    		14:16 7 Sep '09  
    GeneralRe: Please REJECT this article Pin
    xox_c0bra_xox    		14:24 7 Sep '09  
    GeneralI want to Understand METAFILEPICT format Pin
    anirudhas    		21:57 1 Mar '03  
    Last Visit: 3:23 24 Nov '09     Last Update: 3:23 24 Nov '09 12 Next »


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