How do I add vertical scrollbar to a fullscreen win32 console? - c++

Question

When I set my win32 console to full screen, the vertical scrollbar disappears. When the text goes to the bottom of the screen, it does not scroll up. Newly written output is not presented to the user because it is below.
This is the style:
if (isFullScreen)
{
// Set the full screen window style.
style = GetWindowLong(handle, GWL_STYLE);
style &= ~(WS_BORDER | WS_CAPTION | WS_THICKFRAME | WS_OVERLAPPEDWINDOW);
SetWindowLong(handle, GWL_STYLE, style);
// Minimalize, then show maximized to avoid the cursor blink bug in conhost.exe.
ShowWindow(handle, SW_MINIMIZE);
ShowWindow(handle, SW_SHOWMAXIMIZED);
// Set the font size
setFontSize(fontSize);
}
I searched the web but it's understandably not common.
How can I add the vertical scrollbar to this while in full screen?

Answer 1

On my computer, I can realize the appearance of full screen console and vertical scrollbar. My system is Win10, using vs2017.
This is my code.
#include "pch.h"
#include <iostream>
#include <Windows.h>
void full_screen()
{
HWND hwnd = GetForegroundWindow();
int cx = GetSystemMetrics(SM_CXSCREEN); /* Screen width pixels */
int cy = GetSystemMetrics(SM_CYSCREEN); /* Screen Height Pixel */
LONG l_WinStyle = GetWindowLong(hwnd, GWL_STYLE); /* Get window information */
/* Set window information to maximize the removal of title bar and border*/
SetWindowLong(hwnd, GWL_STYLE, (l_WinStyle | WS_POPUP | WS_MAXIMIZE) & ~WS_CAPTION & ~WS_THICKFRAME & ~WS_BORDER);
SetWindowPos(hwnd, HWND_TOP, 0, 0, cx, cy, 0);
}
int main()
{
full_screen();
while(1)
{
std::cout << "Hello World!\n";
}
return 0;
}
Debug Result:

Answer 2

The official way to set a console to fullscreen is to call SetConsoleDisplayMode().
Under Windows 10 Pro Version 1803 the following code shows a vertical scrollbar without further ado:
#include <iostream>
#include <windows.h>
int main()
{
HANDLE const hConsole = ::GetStdHandle( STD_OUTPUT_HANDLE );
if( hConsole == INVALID_HANDLE_VALUE ||
! ::SetConsoleDisplayMode( hConsole, CONSOLE_FULLSCREEN_MODE, nullptr ) )
{
DWORD const err = ::GetLastError();
std::cerr << "Failed to set console fullscreen mode. System error: " << err << "\n";
return 1;
}
for( int i = 0; i < 200; ++i )
{
std::cout << "Hello World!\n";
}
return 0;
}
Note that SetConsoleDisplayMode() can fail if the process is not attached to a console (e. g. by passing the flag CREATE_NO_WINDOW to CreateProcess()) or if STDOUT is redirected to a file.