Random Class

Question

I have an array of numbers. The numbers CAN be non-sequential (123515). What I want to do is to use the Random class to pick one of this numbers randomly. From what I have seen of the Random class it only picks random numbers between two values (and it's not possible to exclude any specific numbers). Can anyone help. Thanks

Administrator · Answer

Yeah I'm sorry. I was pretty tired when I read your code the first time. Looking at it now I understand it. It is VERY simple so I guess I must have been VERY tired :) Thanks.

Administrator · Answer

No it wont. It will first return a random number between 0-5 and then look at your array at the position of the random number and return the number at that offset in your array. Best thing to do would be for you to make a small console application using this concept and run it under the debugger until you understand what's being done.

Administrator · Answer

So just to make sure: if I have an array with the following numbers (123203050) and use the code you provided it will not return for example 4 5 10 or 45? Thanks guys!

Administrator · Answer

use myArray.Length to get the ceiling not count as in my code sample.

Administrator · Answer

Ok. using System; Random random = new Random() // declare and fill your array ... int ceiling = myArray.Count; // How many elements in your array int arrayIndex = random.Next(ceiling); // Grab a random # between zero and ceiling int myRandom = myArray[arrayIndex]; // Whats the value in your array at the rand index?

Administrator · Answer

Here you go: using System; class RandomEx { static void Main() { int[] numbers = {12345}; Random r = new Random(); for(int i = 0; i < 20; i++) Console.WriteLine(numbers[r.Next(numbers.GetLowerBound(0) numbers.Length)]); } }