MFC单文档位图显示问题
CClientDC dc(this);
CDC *mdc=new CDC;
mdc->CreateCompatibleDC(&dc);
CBitmap bitmap;
bitmap.m_hObject=(HBITMAP)::LoadImage(NULL,filename,IMAGE_BITMAP,0,0,LR_LOADFROMFILE);
mdc->SelectObject(bitmap);
CRect rect;
GetClientRect(&rect);
dc.BitBlt(0,0,rect.right,rect.bottom,mdc,0,0,SRCCOPY);
在OnDraw里添加上面的代码,为什么无法显示位图?