加载图片并显示。。。窗口一片空白。。。



图片已加载显示，超过256色，没法编辑。不过程序应该照样可以显示，这应该不是问题。。

是不是图片的宽度高度什么的没设置对？？

急。。

大家帮忙哦。。。先谢谢了。。



#include <windows.h>
#include <wingdi.h>

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("HelloWin") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;

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.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;

if (!RegisterClass (&wndclass))
{
MessageBox (NULL, TEXT ("This program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

hwnd = CreateWindow (szAppName, // window class name
TEXT ("The Hello Program"), // window caption
WS_OVERLAPPEDWINDOW, // window style
CW_USEDEFAULT, // initial x position
CW_USEDEFAULT, // initial y position
CW_USEDEFAULT, // initial x size
CW_USEDEFAULT, // initial y size
NULL, // parent window handle
NULL, // window menu handle
hInstance, // program instance handle
NULL) ; // creation parameters

ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;



while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
HDC hdcMem, hdc ;
PAINTSTRUCT ps ;
HBITMAP bitmap,IDB_BITMAP1;//定义bitmap对象
BITMAP bmp;
HINSTANCE hInst,hInstance;



switch (message)
{
case WM_CREATE:


InvalidateRect(hwnd,NULL,TRUE);

return 0 ;

case WM_PAINT:



hdc=BeginPaint(hwnd,&ps);

hdcMem=CreateCompatibleDC(NULL);

bitmap=LoadBitmap( hInstance,MAKEINTRESOURCE(IDB_BITMAP1));

GetObject(bitmap,sizeof(bmp),&bmp);//获得bitmap信息到bmp结构中;

SelectObject(hdcMem,bitmap);//将BMP选入到内存DC中

DeleteObject(bitmap);//删除对象

//StretchBlt(hdc,0,0,500/4,500/4,hdcMem,0,0,500/4,500/4,WHITENESS );

BitBlt(hdc,0,0,500/4,500/4,hdcMem,0,0,SRCINVERT);//将内存DC中的内容拷贝到当前窗口DC中,并显示


DeleteDC(hdcMem);//删除DC；

EndPaint(hwnd,&ps);

return 0 ;

case WM_DESTROY:
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

[解决办法]
修改后的代码，本地跑ok的。
需要添加一个叫IDB_BITMAP1的资源。

C/C++ code

#include <windows.h>#include <wingdi.h>#include "resource.h"LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,                    PSTR szCmdLine, int iCmdShow){    static TCHAR szAppName[] = TEXT ("HelloWin") ;    HWND hwnd ;    MSG msg ;    WNDCLASS wndclass ;    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.hCursor = LoadCursor (NULL, IDC_ARROW) ;    wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;    wndclass.lpszMenuName = NULL ;    wndclass.lpszClassName = szAppName ;    if (!RegisterClass (&wndclass))    {        MessageBox (NULL, TEXT ("This program requires Windows NT!"),              szAppName, MB_ICONERROR) ;        return 0 ;    }    hwnd = CreateWindow (szAppName, // window class name        TEXT ("The Hello Program"), // window caption        WS_OVERLAPPEDWINDOW, // window style        CW_USEDEFAULT, // initial x position        CW_USEDEFAULT, // initial y position        CW_USEDEFAULT, // initial x size        CW_USEDEFAULT, // initial y size        NULL, // parent window handle        NULL, // window menu handle        hInstance, // program instance handle        NULL) ; // creation parameters    ShowWindow (hwnd, iCmdShow) ;    UpdateWindow (hwnd) ;    while (GetMessage (&msg, NULL, 0, 0))    {        TranslateMessage (&msg) ;        DispatchMessage (&msg) ;    }    return msg.wParam ;}LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam){    HDC hdcMem, hdc ;    PAINTSTRUCT ps ;    HBITMAP bitmap;//定义bitmap对象    BITMAP bmp;    HINSTANCE hInst,hInstance;    switch (message)    {    case WM_CREATE:        InvalidateRect(hwnd,NULL,TRUE);        return 0 ;    case WM_PAINT:        hdc=BeginPaint(hwnd,&ps);        hdcMem=CreateCompatibleDC(hdc);        bitmap=LoadBitmap( (HINSTANCE)GetModuleHandle(NULL),MAKEINTRESOURCE(IDB_BITMAP1));        GetObject(bitmap,sizeof(bmp),&bmp);//获得bitmap信息到bmp结构中;        SelectObject(hdcMem,bitmap);//将BMP选入到内存DC中        //StretchBlt(hdc,0,0,500/4,500/4,hdcMem,0,0,500/4,500/4,WHITENESS );        BitBlt(hdc,0,0,500/4,500/4,hdcMem,0,0,SRCCOPY);//将内存DC中的内容拷贝到当前窗口DC中,并显示        DeleteObject(bitmap);//删除对象        DeleteDC(hdcMem);//删除DC；        EndPaint(hwnd,&ps);        return 0 ;    case WM_DESTROY:        PostQuitMessage (0) ;        return 0 ;    }    return DefWindowProc (hwnd, message, wParam, lParam) ;}