问一个很简单的问题，为什么文本没法显示！

Question

void  CListMemberWnd::OnPaint()    
{  
           CPaintDC  dc(this);  
           CRect  rect;  
           this->GetClientRect(&rect);  
 
           CDC*   pDCMem  =  new  CDC;  
           pDCMem->CreateCompatibleDC(  &dc  );  
 
           pDCMem->TextOut(0,0,  "abc");  
           pDCMem->Draw3dRect(  rect,  RGB(0,0,0),  RGB(0,0,0)  );      
 
           dc.BitBlt(  0,  0,  rect.Width(),  rect.Height(),  pDCMem,  0,  0,  SRCCOPY  );  
}  
很简单的函数，可是什么都没法显示，请问为什么？谢谢！ 

Answer 1

try as following:
pDCMem->Draw3dRect(  rect,  RGB(0,0,0),  RGB(0,0,0)  ); 
pDCMem->TextOut(0,0,  "abc");      

Answer 2

加上
CBitmap bmp;
bmp.CreateCompatibleBitmap(&dc, rect.Width(), rect.Height());
CBitmap* pold = pDCMem->SelectObject(&bmp);
建议后面加上
pDCMem->SelectObject(pold);
pDCMem->DeleteDC();
delete pDCMem;

Answer 3

pDCMem应该选入一个Bitmap先：           CDC*   pDCMem  =  new  CDC;  
           pDCMem->CreateCompatibleDC(  &dc  );  
           
           CBitmap *pBitmap = new CBitmap;
           CBitmap *pOldBmp;
           pBitmap->CreateCompatibleBitmap(pDCMem,...);
           pOldBmp = pDCMem->SelectObject(pBitmap);