简单按键指令识别

//windows.h文件中包含应用程序中所需的数据类型和数据结构的定义
#include <windows.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <stdio.h>
#include <math.h>
#define PI acos(-1)
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);//窗口函数说明
//---------以下初始化窗口类--------------
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInst,LPSTR lpszCmdLine,int nCmdShow)
{
    HWND hwnd;
    MSG Msg;
    WNDCLASS wndclass;
    char lpszClassName[] = "窗口";     //窗口类名
    char lpszTitle[] = "My_Windows";    //窗口标题名

    //窗口类的定义
    wndclass.style = CS_HREDRAW | CS_VREDRAW;                  //窗口类型为默认类型
    wndclass.lpfnWndProc = WndProc;      //窗口处理函数为WndProc
    wndclass.cbClsExtra = 0;             //窗口类无扩展
    wndclass.cbWndExtra = 0;             //窗口实例无扩展
    wndclass.hInstance = hInstance;     //当前实例句柄

    wndclass.hIcon = LoadIcon(NULL,IDI_APPLICATION);//窗口的最小化图标为默认图标
    wndclass.hCursor = LoadCursor( NULL, IDC_ARROW); //窗口 采用箭头光标
    wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); //窗口 背景为 白色
    wndclass.lpszMenuName = NULL ; //窗口 中无菜单
    wndclass.lpszClassName = lpszClassName; //窗口类名为“窗口示例”
//-----------以下进行窗口类的注册
    if (!RegisterClass(&wndclass))//如果注册失败则发出警吿声音
    {
        MessageBeep (0);
        return FALSE;
    }

//创建窗口
    hwnd = CreateWindow(
                        lpszClassName, //窗口类名
                        lpszTitle,      //窗口实例的标题名
                        WS_OVERLAPPEDWINDOW, //窗口 的风格
                        CW_USEDEFAULT,
                        CW_USEDEFAULT,  //窗口左上角坐标为默认值
                        CW_USEDEFAULT,
                        CW_USEDEFAULT,  //窗口的髙和宽为默认值
                        NULL,           //此窗口无父窗口
                        NULL,           //此窗口无主菜单
                        hInstance,      //创建此窗口应用程序的当前句柄
                        NULL            //不使用该值
                        );



    ShowWindow( hwnd, nCmdShow);        //显示窗口
    UpdateWindow(hwnd);                 //绘制用户区
    while( GetMessage(&Msg, NULL, 0, 0)) //消息循环
    {
        TranslateMessage(&Msg);
        DispatchMessage(&Msg);
    }
    return Msg.wParam;                  //程序终止时将信息返回系统
}


//窗口函数
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    HDC hDC, hdc_old;
    HBITMAP hBmp;
    RECT rect;
    HBRUSH hBrush;
    PAINTSTRUCT Ps;
    TEXTMETRIC tm;
    HFONT hf;
    HPEN hPen;
    SIZE Sz;
    COLORREF color[7] = {RGB(255,0,0), RGB(255,165,0), RGB(255,255,0), RGB(0,255,0), RGB(0,255,255), RGB(0,0,255), RGB(139,0,255)};
    static bool isshift = false, isctrl = false, isctrlR = false, isshiftB = false, isup = false, isR = false, isG = false, isB = false;
    char *textbuf[] = {
        "您按下了UP键",
        "您按下了CTRL键"
    };
    HBITMAP hBkBmp;
    int i;

    switch (message)
    {
    case WM_KEYDOWN:
        {
            switch (wParam)
            {
            case VK_UP:
                isup = true;
                break;
            case VK_SHIFT:
                isshift = true;
                break;
            case VK_CONTROL:
                isctrl = true;
                break;
            default:
                break;
            }
        }
        return 0;
    case WM_KEYUP:
        InvalidateRect(hWnd, NULL, 1);
        return 0;
    case WM_ERASEBKGND:
        return 1;
    case WM_CHAR:
        if (GetAsyncKeyState(VK_CONTROL)&&GetAsyncKeyState('R'))
        {
            if (isctrl == true)
            {
                isctrlR = true;
                isctrl = false;
            }
        }
        else if (GetAsyncKeyState(VK_SHIFT)&&GetAsyncKeyState('B'))
        {
            if (isshift)
            {
                isshift = false;
                isshiftB = true;
            }
        }
        else if (GetAsyncKeyState('B'))
        {
            isB = true;
        }
        else if (GetAsyncKeyState('R'))
        {
            isR = true;
        }
        else if (GetAsyncKeyState('G'))
        {
            isG = true;
        }

        return 0;
    case WM_PAINT:
        hDC = BeginPaint(hWnd, &Ps);
//        hdc_old = BeginPaint(hWnd, &Ps);
//        hDC = CreateCompatibleDC(hdc_old);
        GetClientRect(hWnd,&rect);
//        hBmp = CreateCompatibleBitmap(hdc_old,rect.right,rect.bottom);
//        SelectObject(hDC,hBmp);

        if (isup)
        {
            hPen = CreatePen(PS_SOLID, 1, RGB(255,255,255));
            hBrush = CreateSolidBrush(RGB(255,255,255));
            SelectObject(hDC, hBrush);
            SelectObject(hDC, hPen);
            Rectangle(hDC, rect.left, rect.top, rect.right, rect.bottom);
            DrawText(hDC, textbuf[0], -1, &rect, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
            isup = false;
        }
        else if (isctrlR)
        {
            hPen = CreatePen(PS_SOLID, 1, color[1]);
            hBrush = CreateSolidBrush(color[1]);
            SelectObject(hDC, hBrush);
            SelectObject(hDC, hPen);
            Rectangle(hDC, rect.left, rect.top, rect.right, rect.bottom);
            isctrlR = false;
        }
        else if (isctrl)
        {
            hPen = CreatePen(PS_SOLID, 1, RGB(255,255,255));
            hBrush = CreateSolidBrush(RGB(255,255,255));
            SelectObject(hDC, hBrush);
            SelectObject(hDC, hPen);
            Rectangle(hDC, rect.left, rect.top, rect.right, rect.bottom);
            DrawText(hDC, textbuf[1], -1, &rect, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
            isctrl = false;
        }
        else if (isshiftB)
        {
            hPen = CreatePen(PS_SOLID, 1, color[6]);
            hBrush = CreateSolidBrush(color[6]);
            SelectObject(hDC, hBrush);
            SelectObject(hDC, hPen);
            Rectangle(hDC, rect.left, rect.top, rect.right, rect.bottom);
            isshiftB = false;
        }
        else if (isR)
        {
            hPen = CreatePen(PS_SOLID, 1, color[0]);
            hBrush = CreateSolidBrush(color[0]);
            SelectObject(hDC, hBrush);
            SelectObject(hDC, hPen);
            Rectangle(hDC, rect.left, rect.top, rect.right, rect.bottom);
            isR = false;
        }
        else if (isG)
        {
            hPen = CreatePen(PS_SOLID, 1, color[3]);
            hBrush = CreateSolidBrush(color[3]);
            SelectObject(hDC, hBrush);
            SelectObject(hDC, hPen);
            Rectangle(hDC, rect.left, rect.top, rect.right, rect.bottom);
            isG = false;
        }
        else if (isB)
        {
            hPen = CreatePen(PS_SOLID, 1, color[5]);
            hBrush = CreateSolidBrush(color[5]);
            SelectObject(hDC, hBrush);
            SelectObject(hDC, hPen);
            Rectangle(hDC, rect.left, rect.top, rect.right, rect.bottom);
            isB = false;
        }


//        BitBlt(hdc_old,0,0,rect.right,rect.bottom,hDC,0,0,SRCCOPY);
//        DeleteObject(hBmp);
        DeleteObject(hBrush);
        DeleteObject(hPen);
//        DeleteDC(hDC);
        ReleaseDC(hWnd, hDC); //释放
        EndPaint(hWnd, &Ps); //结束缓制
        return 0;

    case WM_DESTROY:
        PostQuitMessage(0);                 //调用 PostQuitMessage 发出 WM_QUIT 消息
        return 0;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam); //默认时采用系统消息默认处理函数

    }

}