Moving from VB to C# and stalked

Question

The most boring for me is using GDI in C# after VB. --------- I need to create basic MyControl - Custom (User) Control having the only "Line" method. I want to call this method as MyControl.Line(x1,y1,x2,y2) from the Main Form on Button_Click Event. And no more code in this form for now. -------- And I'm confused about all this Graphics graphics.... With different "Invalidate","Dispose", etc.... -------- Does anybody can help me? Thanx in advance.