VC++ 窗口重绘

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
int wmId, wmEvent;
PAINTSTRUCT ps;
HDC hdc;
/*HBITMAP hbmp,hbmp2;
HDC srchdc,srchdc2;*/
hdc=GetDC(hWnd);
hbmp=LoadBitmap(hInst,(LPCTSTR)IDB_BITMAP1);
srchdc=CreateCompatibleDC(hdc);
SelectObject(srchdc,hbmp);
hbmp1=LoadBitmap(hInst,(LPCTSTR)IDB_BITMAP3);
srchdc1=CreateCompatibleDC(hdc);
SelectObject(srchdc1,hbmp1);
BitBlt(srchdc1,100,100,500,500,srchdc,0,0,SRCCOPY);

switch (message)
{
case WM_COMMAND:
wmId = LOWORD(wParam);
wmEvent = HIWORD(wParam);
// 分析菜单选择:
switch (wmId)
{
case IDM_ABOUT:
DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About);
break;
case IDM_EXIT:
DestroyWindow(hWnd);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
}
break;
case WM_PAINT

VC++关于窗口重绘的问题，急！ vc 多窗口 VC++6.0调试窗口 sendmessage(WM_PAINT)窗口重绘问题 简单vc++窗口程序问题 VC 显示窗口的问题 vc 中重绘窗口到底是什么意思?? vc中窗口通信问题 Vc.net 创建窗口问题 VC++的窗口过程理解