win32 - RegisterRawInputDevices 和 GetRawInputData

RegisterRawInputDevices 可以注冊鼠標或者鍵盤等輸入的信息，然后GetRawInputData可以獲取傳來的WM_INPUT消息中的輸入信息。

代碼參考：

#include <windows.h>
#include <iostream>
using namespace std;
LRESULT CALLBACK WindProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam)
{
    if (Msg == WM_INPUT)
    {
        HRAWINPUT hRawInput = (HRAWINPUT)lParam;
        RAWINPUT input = { 0 };
        UINT size = sizeof(input);
        GetRawInputData(hRawInput, RID_INPUT, &input, &size, sizeof(RAWINPUTHEADER));

        printf("vkey: %x, flag: %d\n", input.data.keyboard.VKey, input.data.keyboard.Flags);
    }
    return DefWindowProc(hWnd, Msg, wParam, lParam);
}

int main()
{
    WNDCLASSEX wcx = { 0 };
    wcx.cbSize = sizeof(WNDCLASSEX);
    wcx.lpfnWndProc = WindProc;
    wcx.hInstance = GetModuleHandle(NULL);
    wcx.lpszClassName = TEXT("RawInputClass");
    RegisterClassEx(&wcx);
    HWND hWnd = CreateWindowEx(0, TEXT("RawInputClass"), NULL, 0, 0, 0, 0, 0, HWND_MESSAGE, NULL, GetModuleHandle(NULL), NULL);

    RAWINPUTDEVICE rid = { 0 };
    rid.usUsagePage = 0x01;
    rid.usUsage = 0x06; //keyboard
    rid.dwFlags = RIDEV_INPUTSINK;
    rid.hwndTarget = hWnd;

    RegisterRawInputDevices(&rid, 1, sizeof(RAWINPUTDEVICE));

    MSG msg;
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    return 0;
}