C# 0 The Complete Reference

PART I

C h a p t e r   1 1 :  

I n h e r i t a n c e  

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PART IPART I

Using sealed to Prevent Inheritance

As powerful and useful as inheritance is, sometimes you will want to prevent it. For 

example, you might have a class that encapsulates the initialization sequence of some 

specialized hardware device, such as a medical monitor. In this case, you don’t want users 

of your class to be able to change the way the monitor is initialized, possibly setting the 

device incorrectly. Whatever the reason, in C# it is easy to prevent a class from being 

inherited by using the keyword 

sealed

.

To prevent a class from being inherited, precede its declaration with 

sealed

. As you 

might expect, it is illegal to declare a class as both