The term "Polymorphism" is the combination of "poly" + "morphs" which means many forms. It is a greek word. In object-oriented programming, we use 3 main concepts: inheritance, encapsulation and polymorphism.
There are two types of polymorphism in C#: compile time polymorphism and runtime polymorphism. Compile time polymorphism is achieved by method overloading and operator overloading in C#. It is also known as static binding or early binding. Runtime polymorphism in achieved by method overriding which is also known as dynamic binding or late binding.
C# Runtime Polymorphism Example
Let's see a simple example of runtime polymorphism in C#.
C# Runtime Polymorphism Example 2
Let's see a another example of runtime polymorphism in C# where we are having two derived classes.
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Runtime Polymorphism with Data Members
Runtime Polymorphism can't be achieved by data members in C#. Let's see an example where we are accessing the field by reference variable which refers to the instance of derived class.