abstract class FactoryClass

{

    public abstract GetFactoryMethod();

}

​

class factoryA : FactoryClass

{

    override

}

​

FactoryClass fact = null; switch 

( case  "factA"  fact =  new factoryA();

csae "factB"  fact =  new factoryB();

public delegate void myDelegate(int a, int b);

public void Add(int a, int b)

{

    return a + b;

}

​

myDelegate my1 = new myDelegate(Add);

myDelegate my2 = new myDelegate(Sub);

int a = obj.myDelegate(50, 100);

async await employee employeeName A, A, B, B, C, C, D select count( *) as 

employeeCount , employeeName from employee group by employeeName having count( *)  =  1 

employee.Single(e  =>  e.EmployeeName == "D" )