For a vertical or horizontal line you can use a rectangle instead. Otherwise
you are going to have to draw multiple parallel lines to create the illusion
of a single thicker line.
Is it possible to use DLL functions to draw a line with
width > 1. I tried to do so in the full framework and it
works (Graphics.GetHdc(), CreatePen, SelectObject,
MoveToEx, LineTo etc.). But in CF I don't have a DC and no
idea where I can get one.
For a form you can use GetDC which will return the DC for a specified window
handle. You can get the hWnd of the form by calling Focus() and then
P/Invoking the GetFocus API call. These two functions are fairly simple to
P/Invoke:-