What is sealed class in C#?

In today's post i am going to cover "What is Sealed class in C#  "?

Sealed is a keyword to declare a class as sealed.A class which can not be inherited is know as sealed class.

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. A sealed class cannot be used as a base class. For this reason, it cannot also be an abstract class. Sealed classes are primarily used to prevent derivation.

Note:Sealed classes can never be used as base class.

Below code will show how to declare sealed class.

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class CodiBucket         {             static void Main(string[] args)             {                 SealedClass sealedCls = new SealedClass();                 int total = sealedCls.Add(4, 5);                 Console.WriteLine("Total = " + total.ToString());             }         }  // Sealed class sealed class SealedClass {     public int Add(int x, int y)     {         return x + y;     } }

Sealed Method

When an is decorated with a sealed modifier, that method is said to be a sealed method.A sealed method overrides an inherited virtual method with the same signature. A sealed method shall also be marked with the override modifier. Use of the sealed modifier prevents a derived class from further overriding the method.

Here is the example to explain the above sentences.

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class CodiBucket         {             public virtual void Method1()             {                 Console.WriteLine("CodiBucket - Method 1");             }             public virtual void Method2()             {                 Console.WriteLine("CodiBucket - Method 2");             }         }         class Child1 : CodiBucket         {             public sealed override void Method1()             {                 Console.WriteLine("CodiBucket Method 1");             }             public override void Method2()             {                 Console.WriteLine("CodiBucket Method 2");             }         }         class Child2 : Child1         {             public override void Method2()             {                 Console.WriteLine("CodiBucket - Method 2");             }         }

Below i have tired to show how sealed keyword is used to prevent a method to be further overloaded.

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Thanks.