请问一个关于句柄的问题.

Question

changed &memDC to memDC.GetSafeHdc();
then it will ok.

Answer 1

改成这样之后，
TransparentBlt(bitmap,50,50,rect.Width()-20,rect.Height()-20,MemDC.m_hDC,0,0,100,100,50);
它又说
E:\loppp\program\bmp1\bmp1Dlg.cpp(208) : error C2664: 'TransparentBlt' : cannot convert parameter 1 from 'struct HBITMAP__ *' to 'struct HDC__ *'
        Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
Error executing cl.exe.

Answer 2

HDC hdc=CreateCompatibleDC(NULL);SelectObject(bitmap);.........TransparentBlt(hdc,50,50,rect.Width()-20,rect.Height()-20,MemDC.m_hDC,0,0,100,100,50);