using System;

using System.Collections.Generic;       

public class Program

{

    public static void Main()

    {

        //if we want to make a method resuable, we can go with delegates, 

        // extensively used by framework developers to plug the logic that developers want to in to the framework methods

        //if we want to pass method as param to another method then probably we can use pf delagates

        List<Employee> empList = new List<Employee>();

        empList.Add(new Employee(){ID = 101,Name = "Kiran",Experience = 5});

        empList.Add(new Employee(){ID = 102,Name = "Pavan",Experience = 8});

        empList.Add(new Employee(){ID = 101,Name = "sai",Experience = 1});

        // not requires whenusing lambda exressions

        IsPromotable ispromotable = new IsPromotable(promoted);

        Employee.PromotedEmployee(empList,promoted);

        // 

        Employee.PromotedEmployee(empList,emp => emp.Experience >= 5);

    }

    // below function is not necessary for lambsa expressions

    public static bool promoted(Employee emp){ 

        if(emp.Experience >= 5){

            return true;

        }

        return false;

    }

    /*public static void PromotedEmployee( list<employye> employees){

        if(employee.experience > 5){

         Console.Write("promoted")

        }

        // lambda expressions are actually based on delegates

    }*/

​

​

}

// here we r passing a customized method promoted & the signature of this delegate must be same as that method

public delegate bool IsPromotable(Employee emp);

public class Employee {

public string Name {get; set;}

public int Experience{get; set;}

public int ID{get; set;}

public static void PromotedEmployee(List<Employee> emplist, IsPromotable isEligibleToPromote){

        foreach(var emp in emplist){

        if(isEligibleToPromote(emp)){

        Console.Write(emp.Name +  " is promoted, ");

        }

    }

}

​

}

​

​

​

​