How do I roll a dice multiple times without getting same result using the Random method?

Question

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

namespace DieRoller
{
    public class Program
    {
        public static void Main()
        {
            for (int a = 0; a < 20; a = a + 1)
            {
                Console.WriteLine(RollDie());

            }
            Console.ReadLine();
        }

        public static int RollDie()
        {
            Random roll = new Random();
            int test = roll.Next(1, 6 + 1);
            return test;
        }
    }
}

When I execute this code I get the number 4 multiple times or the number 2 multiple times...etc.

Isn't it supposed to execute the RollDie function for each iteration of the loop? and isn't that supposed to yield a different value each time? pls halp!

EDIT: The thing is guys, I need to generate the randomness only inside the RollDie method, and I can't have any arguments for the RollDie method (Basically I have to generate the randomness only using the random method inside the RollDie method), other questions don't address that.

When you create new instances of Random in quick succession they'll often end up with the same seed, resulting in the same values. — Jonathon Chase, Aug 28 '18 at 16:22

score 1 · Accepted Answer · answered Aug 28 '18 at 16:24

See comments for explanation of why it doesn't work. Here a possible way to make it work:

public static void Main()
{
    Random roll = new Random();
    for (int a = 0; a < 20; a = a + 1)
    {
        Console.WriteLine(RollDie(roll));

    }
    Console.ReadLine();
}

public static int RollDie(Random roll)
{
    int test = roll.Next(1, 6 + 1);
    return test;
 }

Or, for simplicity, just:

public static void Main()
{
    Random roll = new Random();
    for (int a = 0; a < 20; a = a + 1)
    {
        Console.WriteLine(roll.Next(1, 6 + 1));

    }
    Console.ReadLine();
 }

How do I roll a dice multiple times without getting same result using the Random method?

1 Answers1