Generic & Lambda Expression

gistfile1.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GenericTypeCollection
{
    class Car
    {
        public string Model { get; set; }
        public string PlateNumber { get; set; }
        public int Age { get; set; }
    }
    class Person
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public int Age { get; set; }
        public string Gender { get; set; }

        public Person()
        {

        }

        public Person(string firstName, string lastName, int age)
        {
            FirstName = firstName;
            LastName = lastName;
            Age = age;
        }

        public override string ToString()
        {
            return string.Format("{0} {1}, {2}", FirstName, LastName, Age);
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            //ArrayList arr = new ArrayList();

            //arr.Add(new Person { FirstName = "Jon", LastName = "Histed", Age = 35 });
            //arr.Add(new Person { FirstName = "Jane", LastName = "Doe", Age = 28 });
            //arr.Add(new Person { FirstName = "John", LastName = "Donald", Age = 34 });
            //arr.Add(new Person { FirstName = "Terry", LastName = "Cassidy", Age = 65 });
            //arr.Add(new Car { Model = "Mustang", PlateNumber = "S 888" });

            //ArrayList filtered = new ArrayList();
            //foreach (Person item in arr)
            //{
            //    if (item.Age < 30)
            //        filtered.Add(item);
            //}

            //foreach (Person item in filtered)
            //{
            //    Console.WriteLine(item);
            //}

            //arr.Add(new Person(age: 23, firstName: "Terry", lastName: "Cassidy"));
            //arr.Add(new Person("Terry", "Cassidy", 35));
            //arr.Add(new Person("Terry", "Cassidy", 35) { Gender = "Male" });

            //foreach (Person item in arr)
            //{
            //    Console.WriteLine(item.FirstName);
            //}

            List<Person> arr = new List<Person>();

            arr.Add(new Person { FirstName = "Jon", LastName = "Histed", Age = 35 });
            arr.Add(new Person { FirstName = "Jane", LastName = "Doe", Age = 28 });
            arr.Add(new Person { FirstName = "John", LastName = "Donald", Age = 34 });
            arr.Add(new Person { FirstName = "Terry", LastName = "Cassidy", Age = 65 });
            //arr.Add(new Car { Model = "Mustang", PlateNumber = "S 888" , Age = 4});


            //var filtered = arr.Where(p => p.Age < 30);



            //Predicate<Person> pre = p => p.Age < 50;

            //var results = Array.FindAll(arr.ToArray(), pre);

            //Func<Person, bool> filter = p =>
            //{
            //    return p.Age > 50;
            //};
            //var filtered = arr.Where(filter);

            //foreach (var item in filtered)
            //{
            //    Console.WriteLine(item);
            //}

            //Action<Person> act = p => Console.WriteLine(p);

            //Action<Person> act = delegate (Person p)
            //{
            //    Console.WriteLine(p);
            //};

            //act(new Person("James", "Bond", 45));

            //Console.WriteLine(filter(new Person { Age = 44 }));

            //Func<int, int, int> calc = (i1, i2) => i1 * i2;

            //Console.WriteLine(calc(5, 6));

            //Func<int, int, int> division = delegate (int i1, int i2) { return i1 / i2; };

            //Console.WriteLine(division(10, 5));
            //var filtered = arr.Where(p => p.Age < 30).ToList();

            //var filtered = (from p in arr.Where(x => x.FirstName.StartsWith("J"))
            //               where p.Age > 30
            //               select new { p.FirstName, p.Age });

            //arr.Add(new Person { FirstName = "Jack", LastName = "Yer", Age = 25 });

            //foreach (var item in filtered)
            //{
            //    Console.WriteLine(item);
            //}


            //DoSomething(delegate (string msg) { Console.WriteLine(msg); });

            //DoSomethingWithAction(delegate (string msg) { Console.WriteLine(msg); });

            //Action<String, int, 



            //DoCalculation((i1, i2) => i1 * i2);

            //DoCalculation((i1, i2) => i1 - i2);

            //DoCalculation(delegate (int i1, int i2) { return i1 + i2; });


            List<Action> acts = new List<Action>();
            for (int i = 0; i < 5; i++)
            {
                var locali = i;
                acts.Add(() => Console.WriteLine(locali));
            }

            foreach (var act in acts)
            {
                act();
            }

            Console.WriteLine("Done");
            Console.Read();


        }

        public static void DoSomething(DoSomethingInAdditional del)
        {
            Console.WriteLine("Doing something internally");

            del("additional stuffs");
        }

        public static void DoSomethingWithAction(Action<String> del)
        {
            Console.WriteLine("Doing something with action internally");

            del("additional stuffs with action");
        }

        public static void DoCalculation(Func<int, int, int> calc)
        {
            Console.WriteLine("Doing something with action internally");
            var i1 = 10;
            var i2 = 4;

            Console.WriteLine(calc(i1, i2));;
        }

        public delegate void DoSomethingInAdditional(string message);
    }
}