//Based on variable and return 'Shape' variable
public static Shape GetObject(int flag)
{
Shape shObj;
if (flag == 1) //Let say '1' is for Squar
{
shObj = new Square();
}
else if (flag == 2) //Let say '2' is for Squar
{
shObj = new Rectange();
}
else if (flag == 3) //Let say '3' is for Triange
{
shObj = new Triangle();
}
else
shObj = null;
return shObj;
}
static void Main(string[] args)
{
//----------set some value to abstract class static variables
Shape.counter = 5;
//----------Following statement is not allowed, we can't create Object of abstract class
//Shape shObj = new Shape();
/*----------We can create 'Reference Variable' of abstract class*/
Shape shObj = null;
/*---------Create object of child class and assign it to parent class 'Reference variable' */
Console.WriteLine("--------------Reference Var:Shape, Object:Square-------------------------");
shObj = new Square();
shObj.Show();
shObj.Draw();
shObj.HideMe();
//Call method which takes any object of type 'Shape'
DoSomething(shObj);
Console.WriteLine("-----------------End-------------------------------------");
/*---------Create object of child class and assign it to parent class 'Reference variable' */
Console.WriteLine("--------------Reference Var:Shape, Object:Rectange-------------------------");
shObj = new Rectange();
shObj.Show();
shObj.Draw();
shObj.HideMe();
//Call method which takes any object of type 'Shape'
DoSomething(shObj);
Console.WriteLine("-----------------End-------------------------------------");
/*---------Create object of child class and assign it to parent class 'Reference variable' */
Console.WriteLine("--------------Reference Var:Shape, Object:Triangle-------------------------");
shObj = new Triangle();
shObj.Show();
shObj.Draw();
shObj.HideMe();
//Call method which takes any object of type 'Shape'
DoSomething(shObj);
Console.WriteLine("--------------Type Casting..Reference Var:Triangle, Object:Triangle-------------------------");
//As shObj refering to 'Trainage' object, we can type cast to it 'Triangle'
Triangle triangObj = (Triangle)shObj;
triangObj.Show();
triangObj.Draw();
triangObj.HideMe();
//Call method which takes any object of type 'Shape'
DoSomething(triangObj);
Console.WriteLine("-----------------End-------------------------------------");
/*---------Create object of child class and assign it to child class 'Reference variable' */
Console.WriteLine("--------------Reference Var:Square, Object:Square-------------------------");
Square sqObj = new Square();
sqObj.Show();
sqObj.Draw();
sqObj.HideMe();
//Call method which takes any object of type 'Shape'
DoSomething(sqObj);
Console.WriteLine("-----------------End-------------------------------------");
/*---------Create object of child class and assign it to child class 'Reference variable' */
Console.WriteLine("--------------Reference Var:Rectange, Object:Rectange-------------------------");
Rectange rqObj = new Rectange();
rqObj.Show();
rqObj.Draw();
rqObj.HideMe();
//Call method which takes any object of type 'Shape'
DoSomething(rqObj);
Console.WriteLine("-----------------End-------------------------------------");
/*---------Create object of child class and assign it to child class 'Reference variable' */
Console.WriteLine("--------------Reference Var:Triangle, Object:Triangle-------------------------");
Triangle trObj = new Triangle();
trObj.Show();
trObj.Draw();
trObj.HideMe();
//Call method which takes any object of type 'Shape'
DoSomething(trObj);
Console.WriteLine("-----------------End-------------------------------------");
Console.WriteLine("---------------Custom Object creation----------------------------");
int type = 0;
string choice = "";
do
{
Console.WriteLine("Enter 1 to Create 'Square'");
Console.WriteLine("Enter 2 to Create 'Rectangle'");
Console.WriteLine("Enter 3 to Create 'Triangle'");
//Get a number from user
type = Convert.ToInt32(System.Console.ReadLine());
//Function will return object of type 'Shape' which would be refering to 'Square' or 'Rectange' or 'Trinage'
Shape sObj = GetObject(type);
//Call 'Draw' method. It will be decided at run time based on the available object in 'sObj'
sObj.Draw();
sObj.Show();
Console.Write("Do you want to create again? (Y/N):");
choice = System.Console.ReadLine();
}
while (choice == "Y" || choice == "y");
Console.WriteLine("-----------------End-------------------------------------");
/* 'Object' is base class of every class eventually
* so it can hold reference of object of any calls */
Object o1 = new Object();
Object o2 = new Triangle();
Object o3 = new Square();
Object o4 = new Rectange();
//To stop the console so user presses a key to exit application
System.Console.ReadKey();
}