MFC 对话框添加背景图片

void CMyDialogDlg::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // 用于绘制的设备上下文

SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);

// 使图标在工作区矩形中居中
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
int x = (rect.Width() - cxIcon + 1) / 2;
int y = (rect.Height() - cyIcon + 1) / 2;

// 绘制图标
dc.DrawIcon(x, y, m_hIcon);
}
else
{
//
// 给窗体添加背景
//
CPaintDC dc(this);
CRect rc;
GetClientRect(&rc);
CDC dcMem;
dcMem.CreateCompatibleDC(&dc);
CBitmap bmpBackground;
bmpBackground.LoadBitmap(IDB_BITMAP1);

BITMAP bitmap;
bmpBackground.GetBitmap(&bitmap);
CBitmap* pbmpPri = dcMem.SelectObject(&bmpBackground);
dc.StretchBlt(0,0,rc.Width(), rc.Height(), &dcMem,0,0,bitmap.bmWidth, bitmap.bmHeight, SRCCOPY);
}
}