C# RNG - Creating Dice Roller - Unexpected results *Solved*

Hello!
I'm trying to create an simple text based RPG,
for this I need some random nummbers between x and y where x and y varies depending on which dice is needed.
I have multipple dices like D6 (ranging from 1 to 6) and D20(ranging from 1 to 20)
so I decided to use the .Net 's rng and just make functions like D6 and D20 to call for a random nummber between x and y.
but I'm getting some strange output, heres the code, then the outputs.
NB: The code is cut out, this is all the code used for the RNG and dices,
I excluded the rest since it's not relevant in any way
From Dices.cs
static class Dices
{
static public int D6()
{
return randomNummber(1, 6);
}
static public int randomNummber(int min, int max)
{
Random random = new Random();
return random.Next(min, max);
}
And heres the Program.cs code:
int dice = Dices.D6();
Console.WriteLine(dice);
Console.ReadLine();
dice = Dices.D6();
Console.WriteLine(dice);
Console.ReadLine();
This reuslts in the following output example:
1
4
but if I do like this:
dice = Dices.D6();
Console.WriteLine(dice);
int dice = Dices.D6();
Console.WriteLine(dice);
dice = Dices.D6();
Console.WriteLine(dice);
Console.ReadLine();
dice = Dices.D6();
Console.WriteLine(dice);
int dice = Dices.D6();
Console.WriteLine(dice);
dice = Dices.D6();
Console.WriteLine(dice);
Console.ReadLine();
dice = Dices.D6();
Console.WriteLine(dice);
Console.ReadLine();
Using Multipple dice rolls without ReadLine between each results in them being the same:
This would for example output; 1,1,1 4,4,4 ,2
All that is generated after the first one in a row is the same for some reason,
if I use the debug and jump into the code and follow it step by step,
it generates random nummbers anyways:O
anyone has any suggestion to what I can do different?

2 Replies

Know the answer? Post it — somebody with the same question will find it here.

Vulpes15y ago
Accepted answer
Well, one thing I notice straightaway is this line:

return randomNummber(1, 6);

That will produce a random number between 1 and 5 (not 1 and 6) because the endpoint 6 isn't included in the range.

See the docs for the Random.Next() method (http://msdn.microsoft.com/en-us/library/zd1bc8e5.aspx).

Also, rather than create a new Random object every time which can cause repetition problems, it's best to cache a single Random object in a static field and use that:

static private Random random = new Random();

static public int randomNummber(int min, int max)
{
return random.Next(min, max);
}

So I'd try making these changes and see if they solve your problem.
Mazetar15y ago
Thanks a lot:) yea this solved the problem, also the documentation gave me an quite interesting read, thanks:)