Win32 SDK 显示图像

#include <Windows.h>

#include <OCIdl.h>

#include <OleCtl.h>





BOOL DrawPicture(char* pszFilePath,HWND hWnd,int nDrawWidth,int nDrawHeight)

{

    HDC hDC = GetDC(hWnd);

    if(hDC == NULL)

    {

        return GetLastError();

    }

    

    IPicture* pPic = NULL;

    IStream* pStream = NULL;

    int ret = 0;

    HANDLE hFile = NULL;

    DWORD dwFileSize = 0;

    DWORD dwByteRead = 0;

    LPVOID pvData = NULL;

    HGLOBAL hMem = NULL;

    

    hFile = CreateFile(pszFilePath, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

    if (hFile == INVALID_HANDLE_VALUE)

        goto exit;



    dwFileSize = GetFileSize(hFile, NULL);

    if (dwFileSize == INVALID_FILE_SIZE)

        goto exit;

    

    hMem = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);

    if (hMem == NULL)

        goto exit;

    

    pvData = GlobalLock(hMem);

    

    if(!ReadFile(hFile, pvData, dwFileSize, &dwByteRead,NULL) || dwByteRead !=dwFileSize)

    {

        goto exit;

    }

    

    GlobalUnlock(hMem);

    

    CreateStreamOnHGlobal(hMem, TRUE, &pStream);



    ret = OleLoadPicture(pStream, dwFileSize, TRUE, IID_IPicture, (LPVOID*)&pPic);

    

    if(ret != S_OK)

        goto exit;

    

    OLE_XSIZE_HIMETRIC picWidth;

    OLE_YSIZE_HIMETRIC picHeight;

    pPic->get_Width(&picWidth);

    pPic->get_Height(&picHeight);

    

    ret = pPic->Render(hDC, 0, 0, nDrawWidth, nDrawHeight, 0, picHeight, picWidth, -picHeight, NULL);

exit:

    if(hDC)

    {

        ReleaseDC(hWnd, hDC);

        hDC = NULL;

    }

    if(hFile)

    {

        CloseHandle(hFile);

        hFile = NULL;

    }

    if(pPic)

    {

        pPic->Release();

        pPic = NULL;

    }

    if(pStream)

    {

        pStream->Release();

        pStream = NULL;

    }

    if(hMem)

    {

        GlobalFree(hMem);

        hMem = NULL;

    }

    if(ret)

        return TRUE;

    else

        return FALSE;



} 



LRESULT CALLBACK WndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)

{

    switch(uMsg)

    {

    case WM_PAINT:

        {

            PAINTSTRUCT ps = {0};

            BeginPaint(hwnd, &ps);

            RECT rc;

            GetClientRect(hwnd, &rc);

            DrawPicture("H:/Desktop/psu.jpg", hwnd, rc.right-rc.left, rc.bottom-rc.top);            

            EndPaint(hwnd, &ps);

            return 0;

        }



    case WM_CLOSE:

        DestroyWindow(hwnd);

        return 0;



    case WM_DESTROY:

        PostQuitMessage(0);

        return 0;



    default:

        break;

    }



    return DefWindowProc(hwnd, uMsg, wParam, lParam);

}



int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd)

{



    WNDCLASSEX wc = {0};

    wc.cbSize = sizeof(WNDCLASSEX);

    wc.hbrBackground = (HBRUSH)COLOR_WINDOW;

    wc.hCursor = LoadCursor(NULL, IDC_ARROW);

    wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);

    wc.hInstance = hInstance;

    wc.lpfnWndProc = WndProc;

    wc.lpszClassName = "vbgk_class";

    wc.style = CS_VREDRAW | CS_HREDRAW | CS_OWNDC;



    if(!RegisterClassEx(&wc))

    {

        return 1;

    }



    CoInitialize(NULL);



    int cxScreen = GetSystemMetrics(SM_CXSCREEN);

    int cyScreen = GetSystemMetrics(SM_CYSCREEN);



    HWND hwnd = CreateWindowEx(0, "vbgk_class", "Pic Viewer", WS_OVERLAPPEDWINDOW,

        (cxScreen - 900) / 2, (cyScreen - 700) / 2, 900, 700, NULL, NULL, hInstance, NULL);

    if(hwnd == NULL)

    {

        return 2;

    }



    UpdateWindow(hwnd);

    ShowWindow(hwnd, nShowCmd);



    MSG msg;

    BOOL bRet;



    while((bRet = GetMessage(&msg, hwnd, 0, 0)) != 0)

    {

        if(bRet == -1)

            break;

        TranslateMessage(&msg);

        DispatchMessage(&msg);

    }



    return msg.wParam;

}