class Baseclass
{
public void fun()
{
Console.Write("Base class" + " ");
}
}
class Derived1 : Baseclass
{
new void fun()
{
Console.Write("Derived1 class" + " ");
}
}
class Derived2 : Derived1
{
new void fun()
{
Console.Write("Derived2 class" + " ");
}
}
class Program
{
public static void Main(string[] args)
{
Derived2 d = new Derived2();
Derived1 e = new Derived1();
d.fun();
e.fun();
}
}
How can I access the result in Derived 1 and Derived 2 and not the base class Is this overloading or overriding?
new
is neither overloading nor overriding. It essentially says 'When I am called, and the object is cast as Derived1
, then invoke this'. Note that it's when the object is cast , rather than whenever the object is interacted with.
Your code would appear to work, if you had marked the methods as public
. For example:
class Derived1 : Baseclass
{
public new void fun()
{
Console.Write("Derived1 class" + " ");
}
}
class Derived2 : Derived1
{
public new void fun()
{
Console.Write("Derived2 class" + " ");
}
}
Would print
Derived2 class Derived1 class
However, changing your code to the following will reveal the problem with new
in this case:
void Main()
{
Derived2 d = new Derived2();
Derived1 e = new Derived1();
ExecuteIt(d);
ExecuteIt(e);
}
void ExecuteIt(Baseclass obj)
{
obj.fun();
}
Prints
Base class Base class
Since the object is cast as Baseclass
, and thus the hiding doesn't take effect. To properly implement overriding, you need to do the following:
class Baseclass
{
public virtual void fun()
// ^^^^^^^
{
Console.Write("Base class" + " ");
}
}
class Derived1 : Baseclass
{
public override void fun()
// ^^^^^^ ^^^^^^^^
{
Console.Write("Derived1 class" + " ");
}
}
class Derived2 : Derived1
{
public override void fun()
// ^^^^^^ ^^^^^^^^
{
Console.Write("Derived2 class" + " ");
}
}
Which, when run with:
void Main()
{
Derived2 d = new Derived2();
Derived1 e = new Derived1();
ExecuteIt(d);
ExecuteIt(e);
}
void ExecuteIt(Baseclass obj)
{
obj.fun();
}
Properly outputs
Derived2 class Derived1 class
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