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// Author : Tech Point Fundamentals
// Website : www.techpointfunda.com
// Demo : Virtual interface members in C# 8

using System;

interface IBaseInterface // Base or Parent interface
{	
	public virtual void BaseInterfaceVirtualMethod() // Virtual method declared Explicitly by "virtual" keyword
    {
        Console.WriteLine("This is Base Interface - BaseInterfaceVirtualMethod()");
    }	
	protected internal void BaseInterfaceDefaultVirtualMethod() // Default Virtual method without "virtual" keyword
	{
		Console.WriteLine("This is Base Interface : BaseInterfaceDefaultVirtualMethod()");
	}
	public void BaseInterfaceDefaultMethod()
	{
		Console.WriteLine("This is Base Interface : BaseInterfaceDefaultMethod()");
	}
}
interface IDerivedInterface : IBaseInterface // Derived or Child interface
{	
	void IBaseInterface.BaseInterfaceVirtualMethod() // Explicit virtual interface method overriding
    {
        Console.WriteLine("This is Derived Interface : BaseInterfaceVirtualMethod() overridden");
    }	
	abstract void IBaseInterface.BaseInterfaceDefaultVirtualMethod(); // Re-Abstraction : Making virtual method as abstract in derived interface
	public new void BaseInterfaceDefaultMethod() // Base interface virtual method hiding
	{
		Console.WriteLine("This is Derived Interface : BaseInterfaceDefaultMethod() hidden");
	}
	virtual void DerivedInterfaecVirtualMethod()
    {
        Console.WriteLine("This is Derived Interface : DerivedInterfaecVirtualMethod()");
    }	
}

class BaseClass : IBaseInterface // Inheriting class
{	
	void IBaseInterface.BaseInterfaceVirtualMethod() // Explicit virtual method overriding in class
    {
		Console.WriteLine("This is Base Class : BaseInterfaceVirtualMethod() overridden");       
    }	
}
class DerivedClass : IDerivedInterface // Inheriting class
{    
	void IBaseInterface.BaseInterfaceDefaultVirtualMethod() // Implementing abstract overriden member in the inheriting class
    {
       Console.WriteLine("This is Derived Class : abstract BaseInterfaceDefaultVirtualMethod() overridden");        
    }	
	
	public void DerivedInterfaecVirtualMethod() // This method will neither hiding nor overridding the "DerivedInterfaecVirtualMethod" virtual method of inheritted interface "IDerivedInterface"
    {
        Console.WriteLine("This is Derived Class : DerivedInterfaecVirtualMethod()");
    }	
}
					
public class Program
{
	public static void Main()
	{
		IBaseInterface _iBaseClass = new BaseClass();
		Console.WriteLine("\n\n ****** Base Class Method Invocation ******* \n");	
		_iBaseClass.BaseInterfaceVirtualMethod(); // This will call overridden definition of class not the interface
		_iBaseClass.BaseInterfaceDefaultVirtualMethod(); // This will called the default virtual method definition of interface		
	
		
		IDerivedInterface _iDerivedClass = new DerivedClass();
		DerivedClass _DerivedClass = new DerivedClass();
		Console.WriteLine("\n\n ****** Derived Class Method Invocation ******* \n");	
		_iDerivedClass.BaseInterfaceVirtualMethod(); // This will call the overridden definition of derived interface 	
		_iDerivedClass.BaseInterfaceDefaultVirtualMethod(); // This will call the overridden method definition of class
		_iDerivedClass.DerivedInterfaecVirtualMethod(); // This will call the base derived interface definition not the class
		_DerivedClass.DerivedInterfaecVirtualMethod(); // This will call the class defined method not the inheriting interface
		_iDerivedClass.BaseInterfaceDefaultMethod(); // This will call the inheriting derived interface method definition, base interface method definition is hidden
		
	}
}

 
// Author : Tech Point Fundamentals
// Website : www.techpointfunda.com
// Demo : Virtual interface members in C# 8
​
using System;
​
interface IBaseInterface // Base or Parent interface
{   
    public virtual void BaseInterfaceVirtualMethod() // Virtual method declared Explicitly by "virtual" keyword
    {
        Console.WriteLine("This is Base Interface - BaseInterfaceVirtualMethod()");
    }   
    protected internal void BaseInterfaceDefaultVirtualMethod() // Default Virtual method without "virtual" keyword
    {
        Console.WriteLine("This is Base Interface : BaseInterfaceDefaultVirtualMethod()");
    }
    public void BaseInterfaceDefaultMethod()
    {
        Console.WriteLine("This is Base Interface : BaseInterfaceDefaultMethod()");
    }
}
interface IDerivedInterface : IBaseInterface // Derived or Child interface
{   
    void IBaseInterface.BaseInterfaceVirtualMethod() // Explicit virtual interface method overriding

2
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{ IdVideogioco = 2, QuantitaTotale = 50 }