Pasting after SetClipboardData() in C++ does not include newlines for Notepad - c++

Question

I'm developing some software which copies a large string to the windows clipboard to paste into some other software. Pasting in the other software does not work, and when I paste into Notepad, the newlines in the initial strings are gone, which is why it is failing to paste in the other software. I know this because when I re-add the newlines to Notepad, and do a Copy, Pasting then works in the other program. When I paste into Wordpad, the newlines are there mysteriously.
I'm using SetClipboardData() in C++ with the CF_TEXT clipboard format type. I've tried using CF_OEMTEXT, CF_DSPTEXT but neither of those work. I saw some documentation on CF_SYLK (Symbolic Link) for spreadsheets, as the software I'm pasting in is similar to a spreadsheet, but I couldn't get that to work either. Below is my code for copying to the clipboard.
void ClipBoardManager::CopyExcelStringToClipBoard(std::string excel_str)
{
OpenClipboard(nullptr);
EmptyClipboard();
HGLOBAL hg = GlobalAlloc(GMEM_MOVEABLE, excel_str.size() + 1);
if (!hg) {
CloseClipboard();
return;
}
memcpy(GlobalLock(hg), excel_str.c_str(), excel_str.size() + 1);
GlobalUnlock(hg);
SetClipboardData(CF_TEXT, hg);
CloseClipboard();
GlobalFree(hg);
}
Any help is appreciated.

Answer 1

The excel_str must have the CRLF line endings. Here is example code to convert string to the good format:
string replaceAll(string in, string replaceIn, string replaceOut)
{
size_t pos = 0;
while(pos < in.size())
{
size_t pos2 = in.find(replaceIn, pos);
if(pos2 != string::npos)
{
in.replace(in.begin() + pos2, in.begin() + pos2 + replaceIn.size(), replaceOut);
pos = pos2 + replaceOut.size();
}
else
break;
}
return in;
}

Answer 2

If your project setup for unicode characters (default setup) - use unicode everywhere and use CF_UNICODETEXT instead CF_TEXT. Or use non unicode - but consistently - and then change project settings.
Code below will copy text with line endings correctly - after end of this program it's possible to paste copied by this program text (with line endings) from clipboard from say notepad:
#include <Windows.h>
BOOL WINAPI ToClipboard(VOID);
int main()
{
ToClipboard();
}
BOOL WINAPI ToClipboard(VOID)
{
LPTSTR lptstrCopy;
HGLOBAL hglbCopy;
if (!OpenClipboard(NULL))
return FALSE;
EmptyClipboard();
// Allocate a global memory object for the text.
wchar_t s[] = L"12345\n6789";
hglbCopy = GlobalAlloc(GMEM_MOVEABLE,
(wcslen(s) + 1) * sizeof(wchar_t));
if (hglbCopy == NULL)
{
CloseClipboard();
return FALSE;
}
lptstrCopy = (LPTSTR)GlobalLock(hglbCopy);
memcpy(lptstrCopy, &s,
(wcslen(s) + 1) * sizeof(wchar_t));
lptstrCopy[sizeof(s)] = (TCHAR)0; // null character
GlobalUnlock(hglbCopy);
SetClipboardData(CF_UNICODETEXT, hglbCopy);
CloseClipboard();
return TRUE;
}