simulate selection in windows C++ - c++

Question

I have this in my Notepad:
hello
I want to simulate selecting in C++ using Windows' keybd_event function.
here is my code:
keybd_event(VK_SHIFT, 0, 0, 0);
for (size_t i = 0; i < 5; i++)
{
keybd_event(VK_LEFT, 0, 0, 0);
keybd_event(VK_LEFT, 0, KEYEVENTF_KEYUP, 0);
}
keybd_event(VK_SHIFT, 0, KEYEVENTF_KEYUP, 0);
but after I run this, it didn't select anything, it just go to the start of the file. Why isn't this working?

Answer 1

Add KEYEVENTF_EXTENDEDKEY will select rightly.
https://learn.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-keybdinput#members
#include <windows.h>
void main()
{
Sleep(2000);
keybd_event(VK_SHIFT, MapVirtualKey(VK_SHIFT, 0), KEYEVENTF_EXTENDEDKEY, 0);
for (size_t i = 0; i < 5; i++)
{
keybd_event(VK_LEFT, 0, 0, 0);
keybd_event(VK_LEFT, 0, KEYEVENTF_KEYUP, 0);
Sleep(20);
}
keybd_event(VK_SHIFT, MapVirtualKey(VK_SHIFT, 0), KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP, 0);
}
Use VK_SHIFT in keybd_event, There is a problem that shift cannot be released，I recommend you use SendInput instead of keybd_event.
For higher-level operations, I also recommend you use UI Automation.
https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-sendinput
https://learn.microsoft.com/en-us/windows/win32/winauto/entry-uiauto-win32