Sending a keyboard input 키 입력 보내기

The SendInput function inserts the events in the INPUT structures serially into the keyboard or mouse input stream.

키보드 입력을 보낸다.

2020/10/17 - [Raspberry Pi & Arduino] - Turn your Arduino Pro Micro into a USB Keyboard - 아두이노 프로 마이크로 USB 키보드 만들기

#include <Windows.h>
#include <iostream>
 
using namespace std;
 
void PrintMenu()
{
    cout << "--- Key sender ---" << endl << endl;
    cout << "0: End" << endl;
    cout << "1: Send left key" << endl;
    cout << "2: Send right key" << endl;
    cout << "3: Send up key" << endl;
    cout << "4: Send down key" << endl;
    cout << "5: Send enter key" << endl;
    cout << "6: Send 'aA'" << endl;
    cout << "Choose: ";
}
 
// Virtual-Key Codes: https://docs.microsoft.com/ko-kr/windows/win32/inputdev/virtual-key-codes
void SendVKcodes(BYTE vk)
{
    Sleep(5000); // Wait for 5 seconds before sending a keycode.
 
    INPUT input;
    ZeroMemory(&input, sizeof(INPUT));
    input.type = INPUT_KEYBOARD;
    input.ki.wVk = vk;
    // A virtual-key code. The code must be a value in the range 1 to 254. If the dwFlags member
    // specifies KEYEVENTF_UNICODE, wVk must be 0.
 
    // input.ki.wScan = vk;
    // A hardware scan code for the key. If dwFlags specifies KEYEVENTF_UNICODE, wScan specifies
    // a Unicode character which is to be sent to the foreground application.
 
    SendInput(1, &input, sizeof(INPUT));
 
    input.ki.dwFlags = KEYEVENTF_KEYUP;
    // If specified, the key is being released. If not specified, the key is being pressed.
    SendInput(1, &input, sizeof(INPUT));
}
 
void SendaA()
{
    Sleep(5000);
 
    // Send 'a'
    INPUT input;
    ZeroMemory(&input, sizeof(INPUT));
    input.type = INPUT_KEYBOARD;
    input.ki.wVk = 0x41;    // a key
    SendInput(1, &input, sizeof(INPUT));
 
    input.ki.dwFlags = KEYEVENTF_KEYUP;
    SendInput(1, &input, sizeof(INPUT));
 
    // Sned 'A'
    input.ki.dwFlags = 0;
    input.ki.wVk = VK_SHIFT;
    SendInput(1, &input, sizeof(INPUT));
 
    input.ki.wVk = 0x41;    // a key
    SendInput(1, &input, sizeof(INPUT));
 
    input.ki.dwFlags = KEYEVENTF_KEYUP;
    SendInput(1, &input, sizeof(INPUT));
 
    input.ki.wVk = VK_SHIFT;
    SendInput(1, &input, sizeof(INPUT));
}
 
int main()
{
    int choice = 1;
 
    while (choice)
    {
        PrintMenu();
        cin >> choice;
 
        switch (choice)
        {
        case 1:
            SendVKcodes(VK_LEFT);
 
            break;
        case 2:
            SendVKcodes(VK_RIGHT);
 
            break;
        case 3:
            SendVKcodes(VK_UP);
 
            break;
        case 4:
            SendVKcodes(VK_DOWN);
 
            break;
        case 5:
            SendVKcodes(VK_RETURN);
 
            break;
 
        case 6:
            SendaA();
 
            break;
        default:
 
            return 0;
        }
    }
 
    return 0;
}

Run the program and choose the key you want to send.

※ Adjust key down duration by adding Sleep() between KEYEVENTF_KEYDOWN and KEYEVENTF_KEYUP.

For short key down duration, give 60~100 to Sleep() for the better result although some keys don't need Sleep() at all for very short key down duration.