using System;

public class Program

{

    delegate double CallAMethod (int r);

    delegate double AreaLambda(int i);

    delegate double AreaFunc(int j);

    public static void Main()

    {

        //=============== Lambda expresssion =========

        AreaLambda a1 = i =>3.14*i*i;

        //=============== Lambda + Func expresssion =========

        // Func<input , output>

        Func<double, double> AreaFunc = j => 3.14 * j*j; 

        Func<int, int> sum1 = a => a+a;

        Action<string> str = s=> Console.WriteLine("My name is" + s);

        Predicate<string> IsGreather = g => g.Length >5;

        // Normal Annonimous method 

        CallAMethod d1 = new CallAMethod(

                           delegate(int r)

                            {

                               return 3.14*r*r;

                            });

​

        Action<string> action1 = Method1;

        Func <int, int , int> func1 = Add;

        Predicate<string> pred1 = IsLogedIn;

        action1("Prabir Choudhury");

         IsLogedIn("admin");

       Console.WriteLine("Pred: "+IsGreather("Prabi"));

       Console.WriteLine("Hello World:  " + IsLogedIn("admin"));

       Console.WriteLine("Func: "+ Add(2,44));

         Console.WriteLine("Anonimoue: "+ d1(7));

        Console.WriteLine("Lambda: "+ a1(9));

      Console.WriteLine("AreaFunc: "+ AreaFunc(8));

      Console.WriteLine("sum1: "+ sum1(8));

     str("Bob Smith");

​

        //======================== Lambda expression 

    }

    // ============= Static Method======================

    public static void Method1(string name)

    {

      Console.WriteLine("Hellow from Method1 "+ name);

    }

​

     // Method returing int

    public static int Add(int x , int y)

    {

        return x+y;

    }

​

       //============= Method returing boolian 

    public static bool IsLogedIn( string uid)

    {

        if(uid=="admin")

        {

            return true;

        }else return false;

    }

​

}