(CSDN Jan 25, 2007)
I have been working on this piece for long and finally make it clear this time. A little bit help for Patterns and Refactorings make things easy again.
Also I use an AutoCompleteComboBox unit for The Code Project done by Matt Berther. Although it is not perfect, I find it useful on .NET 1. on .NET 2.0, AutoComplete is already a feature of ComboBox.
So try it now and stay tuned. The Update 2 is on its way.