Sometimes you might want to implement custom ImageList controls and encounter the fact that the .NET Windows Forms ImageList is marked as sealed. Instead of crying foul here, let's have a look at some of the reasons for this decision.

My latest article "Sealed is Good" shows you ...

• ... the reason for sealing ImageList.
• ... the reason why this is a good thing.
• ... the reason why unsealing it wouldn't help you at all.
• And finally, the reason why unsealing it would demand a complete rewrite of all of System.Windows.Forms.