.NET Windows Forms in a Nutshell

Summary

GDI+ provides a very powerful set of drawing tools. Access to drawing surfaces, whether they are windows, bitmaps, or metafiles, is provided through the Graphics class. This supplies methods for drawing primitive shapes whose visual attributes are specified with Brush and Pen objects. We can augment the set of primitives by building our own composite shapes using the GraphicsPath class. There is special support for text, both for specifying the appearance with the Font class, and for controlling formatting with the StringFormat class. There is also support for creating and displaying predrawn images using either the Bitmap or Metafile classes. Such images can be loaded from disk or created on the fly. Finally, we saw how the Graphics object can automatically apply a transformation to every drawing operation, making it easy to implement features such as scrolling and zooming, and allowing us to draw sheared and rotated elements even with primitives that provide no direct support for this.

All these facilities enable us to exert a very fine level of control over our components’ behavior. In the next two chapters we will see how to further enhance our controls by building in awareness of the development environment, and adding so-called design-time features.