Question

What are sealed classes in C#?

Answer 1

Sealed classes are used to restrict the inheritance feature of object-oriented programming. Once a class is defined as a sealed class, the class cannot be inherited. 

 

In C#, the sealed modifier is used to define a class as sealed. In Visual Basic .NET the Not Inheritable keyword serves the purpose of the sealed class. If a class is derived from a sealed class then the compiler throws an error. 

 

If you have ever noticed, structs are sealed. You cannot derive a class from a struct. 

 

The following class definition defines a sealed class in C#:

1. // Sealed class    
2. sealed class SealedClass    
3. {       
4. }