C# | Base keyword

The base keyword is used to access members of the base class from within a derived class:

- Call a method on the base class that has been overridden by another method

- Specify which base-class constructor should be called when creating instances of the derived class.

A base class access is permitted only in a constructor, an instance method, or an instance property accessor.

It is an error to use the base keyword from within a static method.

In this example, both the base class, Person, and the derived class, Employee, have a method named Getinfo. By using the base keyword, it is possible to call the Getinfo method on the base class, from within the derived class.

C#
public class Person
{
 protected string ssn = "444-55-6666";
 protected string name = "John L. Malgraine";

 public virtual void GetInfo()
    {
        Console.WriteLine("Name: {0}", name);
        Console.WriteLine("SSN: {0}", ssn);
    }
}
class Employee : Person
{
 public string id = "ABC567EFG";
 public override void GetInfo()
    {
 // Calling the base class GetInfo method:
 base.GetInfo();
        Console.WriteLine("Employee ID: {0}", id);
    }
}

class TestClass
{
 static void Main()
    {
        Employee E = new Employee();
        E.GetInfo();
    }
}
/*
Output
Name: John L. Malgraine
SSN: 444-55-6666
Employee ID: ABC567EFG
*/

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