CPaintDC in dialoge

I want some portion of my CDialog to be CPaintDC how?

What do you mean by "to be CPaintDC", do you want only a part of the dialog to be repainted? CPaintDC is used in OnPaint to get a handle to the CDC. Please clarify =)

i want to draw lines in some portions using move to and line to in dialogue box how can i do this drawing

You must only use CPaintDC inside OnPaint. If you want to draw in another function use CClientDC.

CClientDC dc(this);

dc.MoveTo(0,0);
dc.LineTo(100, 100);