i am making a windows form app in c#, I have a for loop which prints 20 elements with a random number between 0 and 500. With this numbers i need to calculate the next numbers. I want to use the variable "numbers[i]" to print it but this doesnt work and the program picks new random numbers. Here is some code:

private void Form1_Load(object sender, EventArgs e)
        {
            CultureInfo ci = new CultureInfo("en-US");
            Thread.CurrentThread.CurrentUICulture = ci;
            Thread.CurrentThread.CurrentCulture = ci;

            int[] numbers = new int[numberOfItems];

            Random random = new Random();
            double total = 0;

            var text = "";
            for (int i = 0; i < numbers.Length; i  )
            {
                numbers[i] = random.Next(501);
                
                beforeLoop.Text  = $"Element {i} = {numbers[i]} \n";
               
        

                total  = numbers[i];

            }
       
        

        }

        private void compare_Click(object sender, EventArgs e)
        {
            int count = 0;
            count  ;
            if (count ==1 ) // knop is maar 1 keer drukbaar
            {
                compare.Enabled = false;
            }

            int[] numbers = new int[numberOfItems];

            Random random = new Random();
            double total = 0;

            for (int i = 0; i < numbers.Length; i  )
            {
                numbers[i] = random.Next(501);
              
                int numberBigger = numbers[i]   10;
                int numberSmaller = numbers[i] - 5;
                total  = numbers[i];
                int number = int.Parse(numberBox.Text);

                if (number > numbers[i])

                {
                    printLabel.Text  = $"Element {i} = {numberBigger}\n";
                }
                else
                {
                    printLabel.Text  = $"Element {i} = {numberSmaller}\n";
                }

            }

CodePudding user response：

You create a new array each time: int[] numbers = new int[numberOfItems]; But numbers should be persistent throughout the life of the app.

public partial class Form1 : Form
{
    // Class fields exist through out the life time of the class object
    int[] numbers;
    int numberOfItems = 20;

    private void Form1_Load(object sender, EventArgs e)
    {
        CultureInfo ci = new CultureInfo("en-US");
        Thread.CurrentThread.CurrentUICulture = ci;
        Thread.CurrentThread.CurrentCulture = ci;

        // Create the array and fill with random nums ONCE
        numbers = new int[numberOfItems];
        Random random = new Random();
        for (int i = 0; i < numbers.Length; i  )
        {
            numbers[i] = random.Next(501);
            beforeLoop.Text  = $"Element {i} = {numbers[i]}{Environment.NewLine}";
        }
    }

    private void compare_Click(object sender, EventArgs e)
    {
        compare.Enabled = false;
        int number = int.Parse(numberBox.Text);
        for (int i = 0; i < numbers.Length; i  )
        {
            if (number <= numbers[i])
            {
                numbers[i]  = 10;
            }
            else
            {
                numbers[i] -= 5;
            }
            printLabel.Text  = $"Element {i} = {numbers[i]}{Environment.NewLine}";
        }
    }
}