Sealed classes are used to restrict the inheritance feature of object oriented programming. Once a class is defined as sealed class, this class cannot be inherited.
In C#, the sealed modifier is used to define a class as sealed. In Visual Basic .NET, NotInheritable keyword serves the purpose of sealed. If a class is derived from a sealed class, compiler throws an error.
If you have ever noticed, structs are sealed. You cannot derive a class from a struct.
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