Sealed Classes and Sealed Methods

• Sealed Classes: A Class which is defined by using the sealed modifier is a sealed class but if any class is declared as sealed the class cannot be inherited by any other class 

           for example:

           sealed class class1

           class2:class1    //Invalid

Note: We can still consume a sealed class from any other class by creating the object even if inheritance is not possible.

• Sealed Methods: A method which cannot be overridden under child classes is called as Sealed Methods and by default every method of a class is a sealed method because overriding a child class under parent class is possible only when the method is declared as virtual.

            If a method is declared as virtual under a class, any child class of the class linear hierarchy has a right to override the method. 

       class1

       public virtual void show()

       class2:class1    

       public override void show()

       class3:class2

       public override void show()

Note: In the above case even if class2 does not override the method then also class3 can override the method.