using System;

using System.Collections.Generic;

​

public static class ListExt

{

    public static T randomElement<T>(this List<T> list)

    {

        Random ran = new Random();

        int randomIndex = ran.Next(list.Count - 1);

        return list[randomIndex];

    }

}

​

public class Program

{

    public static void Main()

    {

        List<int> intList = new List<int> {1,2,3,4,5,6 };

        List<double> doubleList = new List<double> {0.4, 0.6,0.8,4.5,0.2 };

        var randomInt = getRandomElement(intList);

        var randomDouble = getRandomElement(doubleList);

        Console.WriteLine(randomInt);

        Console.WriteLine(randomDouble);

        //Extension method

        Console.WriteLine(intList.randomElement());

        Console.WriteLine(doubleList.randomElement());

    }

​

    public static T getRandomElement<T>(List<T> list)

    {

        Random ran = new Random();

        int randomIndex = ran.Next(list.Count - 1);

        return list[randomIndex];

    }

}