Copy text to Clipboard in MFC - c++

Question

I tried to make a quick method to set the clipboard text in MFC, but this does not work.
void CopyTextToClipBoard( CString strText)
{
if (OpenClipboard(GetFrame()->GetSafeHwnd()))
{
EmptyClipboard() ;
SetClipboardData (CF_TEXT, strText.GetBuffer() ) ;
CloseClipboard () ;
}
}
I get a 'Windows breakpoint' error at 'setClipboardData'. Anyone know what I might have done wrong?
Edit: Thanks for your comment. Modfied. Now it fails at: memcopy function.
void CopyTextToClipBoard( CString strText)
{
if (OpenClipboard(GetFrame()->GetSafeHwnd()))
{
HGLOBAL hglbCopy;
LPTSTR lptstrCopy;
hglbCopy = GlobalAlloc(GMEM_MOVEABLE, (strText.GetLength() + 1) * sizeof(TCHAR));
if (hglbCopy == NULL)
{
CloseClipboard();
return ;
}
memcpy(GlobalLock(hglbCopy), &strText, strText.GetLength() + 1 * sizeof(TCHAR));
GlobalUnlock(hglbCopy);
SetClipboardData(CF_TEXT, hglbCopy);
EmptyClipboard() ;
SetClipboardData (CF_TEXT, strText.GetBuffer() ) ;
CloseClipboard () ;
}
}
Edit: Using this old msdn example.
const char* output = "Test";
const size_t len = strlen(output) + 1;
HGLOBAL hMem = GlobalAlloc(GMEM_MOVEABLE, len);
memcpy(GlobalLock(hMem), output, len);
GlobalUnlock(hMem);
OpenClipboard(0);
EmptyClipboard();
SetClipboardData(CF_TEXT, hMem);
CloseClipboard();

Answer 1

This is a working one - unicode.
void CopyToClipboard(HWND owner, const std::wstring &w)
{
if (OpenClipboard(owner))
{
HGLOBAL hgClipBuffer = nullptr;
std::size_t sizeInWords = w.size() + 1;
std::size_t sizeInBytes = sizeInWords * sizeof(wchar_t);
hgClipBuffer = GlobalAlloc(GHND | GMEM_SHARE, sizeInBytes);
if (!hgClipBuffer)
{
CloseClipboard();
return;
}
wchar_t *wgClipBoardBuffer = static_cast<wchar_t*>(GlobalLock(hgClipBuffer));
wcscpy_s(wgClipBoardBuffer, sizeInWords, w.c_str());
GlobalUnlock(hgClipBuffer);
EmptyClipboard();
SetClipboardData(CF_UNICODETEXT, hgClipBuffer);
CloseClipboard();
}
}
(Should be correct, wrote on phone)

Answer 2

From the MSDN documentation of SetClipboardData(uFormat,hMem)
If the hMem parameter identifies a memory object, the object must have
been allocated using the function with the GMEM_MOVEABLE flag
You can do that like this:
LPTSTR lptstrCopy;
HGLOBAL hglbCopy;
unsigned int strSize=strText.GetLength();//get your string lenght
hglbCopy = GlobalAlloc(GMEM_MOVEABLE, (strSize+1) * sizeof(TCHAR));//allocate the memory object with GMEM_MOVEABLE
if (hglbCopy == NULL)
{
CloseClipboard();
//other error handling
}
lptstrCopy = (LPTSTR)GlobalLock(hglbCopy);
memcpy(lptstrCopy, strText.GetBuffer(), strSize * sizeof(TCHAR)); //copy the text data
lptstrCopy[strSize] = (TCHAR) 0;//the null terminator
GlobalUnlock(hglbCopy);
EmptyClipboard() ;
SetClipboardData (CF_TEXT,hglbCopy);
CloseClipboard () ;

Answer 3

The second parameter of SetClipboardData is a handle to a global memory block.
See
http://www.codeproject.com/Articles/2242/Using-the-Clipboard-Part-I-Transferring-Simple-Tex
for a detailed explanation.