【转】WINAPI 读取位图Bitmap

//------------------------------------------------------------------------------ 
//  Copyright (c) 2009 eryar All rights reserved. 
// 
//      File    :   Main.cpp 
//      Author  :   eryar@163.com 
//      Date    :   2009-9-18 23:04 
//      Version :   1.0v 
// 
//  Description :    
// 
//============================================================================== 
 
#include <windows.h> 
 
#define IDM_FILE_OPEN   10000 
#define IDM_FILE_EXIT   10001 
 
CHAR*   g_szAppName =   "Read Bitmap"; 
CHAR*   g_szClassName   =   "CReadBMP"; 
HINSTANCE   g_hInst; 
 
void            TrackMenu(HWND hWnd, POINT point); 
LRESULT CALLBACK    WndProc(HWND, UINT, WPARAM, LPARAM); 
int WINAPI      WinMain( 
            HINSTANCE   hInstance, 
            HINSTANCE   hPrevInstance, 
            LPSTR       lpCmdLine, 
            int     nShowCmd) 
{ 
 
    MSG     Msg; 
    HWND        hWnd; 
    WNDCLASSEX  wndclass; 
 
    wndclass.cbSize     =   sizeof(WNDCLASSEX); 
    wndclass.style      =   CS_HREDRAW|CS_VREDRAW; 
    wndclass.lpfnWndProc    =   WndProc; 
    wndclass.cbClsExtra =   0; 
    wndclass.cbWndExtra =   0; 
    wndclass.hInstance  =   hInstance; 
    wndclass.hIcon      =   LoadIcon(NULL, IDI_APPLICATION); 
    wndclass.hIconSm    =   LoadIcon(NULL, IDI_APPLICATION); 
    wndclass.hCursor    =   LoadCursor(NULL, IDC_ARROW); 
    wndclass.hbrBackground  =   NULL;                   //(HBRUSH)GetStockObject(BLACK_BRUSH); 
    wndclass.lpszMenuName   =   NULL; 
    wndclass.lpszClassName  =   g_szClassName; 
 
    if (!RegisterClassEx(&wndclass)) { 
        MessageBox(NULL, "register class failed!  ", g_szAppName, MB_OK|MB_ICONERROR); 
        return false; 
    } 
 
    hWnd            =   CreateWindowEx( 
                        NULL, 
                        g_szClassName, 
                        g_szAppName, 
                        WS_OVERLAPPEDWINDOW, 
                        0,0, 
                        300, 300, 
                        NULL, 
                        NULL, 
                        hInstance, 
                        NULL); 
    if (!hWnd) { 
        MessageBox(NULL, " create window failed!  ", g_szAppName, MB_OK|MB_ICONERROR); 
        return false; 
    } 
 
    g_hInst =   hInstance; 
 
    ShowWindow(hWnd, nShowCmd); 
    UpdateWindow(hWnd); 
 
    while(GetMessage(&Msg, NULL, 0, 0)) { 
        TranslateMessage(&Msg); 
        DispatchMessage(&Msg); 
    } 
 
    return Msg.wParam; 
} 
 
 
LRESULT CALLBACK    WndProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam) { 
    PAINTSTRUCT ps; 
 
    static  RECT    rect; 
    static  HDC hDC; 
    static  HDC hDCBackBuffer; 
    static  HBITMAP hBitmap; 
    static  HBITMAP hOldBitmap; 
 
    switch(Msg) { 
    case    WM_CREATE: { 
        GetClientRect(hWnd, &rect); 
 
    } 
        return 0; 
 
    case    WM_RBUTTONUP: { 
        POINT       point; 
        point.x     =   LOWORD(lParam); 
        point.y     =   HIWORD(lParam); 
        ClientToScreen(hWnd, &point); 
        TrackMenu(hWnd, point); 
    } 
        return 0; 
 
    case    WM_PAINT: 
        GetClientRect(hWnd, &rect); 
        hDC =   BeginPaint(hWnd, &ps); 
        hBitmap =   (HBITMAP)LoadImage(g_hInst, "Demo.bmp", IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE|LR_CREATEDIBSECTION); 
        hDCBackBuffer   =   CreateCompatibleDC(NULL); 
        hOldBitmap  =   (HBITMAP)SelectObject(hDCBackBuffer, hBitmap); 
        BitBlt(hDC, 0, 0, rect.right, rect.bottom, hDCBackBuffer, 0, 0, SRCCOPY); 
 
        EndPaint(hWnd, &ps); 
        return 0; 
 
    case    WM_DESTROY: 
        // keep it clear 
        SelectObject(hDCBackBuffer, hOldBitmap); 
        DeleteDC(hDCBackBuffer); 
        DeleteObject(hBitmap); 
        PostQuitMessage(0); 
        return 0; 
    default: 
        return DefWindowProc(hWnd, Msg, wParam, lParam); 
    } 
} 
 
 
void    TrackMenu(HWND hWnd, POINT point) 
{ 
    HMENU       hMenu; 
    HMENU       hMenuPopup; 
 
    hMenu       =   CreatePopupMenu(); 
    hMenuPopup  =   CreatePopupMenu(); 
    AppendMenu(hMenuPopup, MF_STRING, IDM_FILE_OPEN, "&Open"); 
    AppendMenu(hMenu, MF_POPUP,(UINT)hMenuPopup, "&File"); 
    AppendMenu(hMenu, MF_SEPARATOR, 0, NULL); 
    AppendMenu(hMenu, MF_STRING, IDM_FILE_EXIT, "&Exit"); 
     
    TrackPopupMenu(hMenu, TPM_RIGHTBUTTON, point.x, point.y, 0, hWnd, NULL); 
}