How to count the total amount of integers in a list box and display them into a label C#

Question

Within my system in C# I have a list box that the user can add up to 30 integers into. I have also added 5 different labels, these being: maximum entries allowed:, first value:, middle value:, last value:, and Count:, count being the total amount of integers that are in the list box. I am looking to see how to code these labels so that the values are displayed in each label. Can anyone help? This is the code that I have for the 'Add integer to list box'.

 int acceptedNum = 0;
 if (txtInsert.Text != "")
 {
    if (lstIntegers.Items.Contains(txtInsert.Text))
    {
       if (!(int.TryParse(txtInsert.Text, out acceptedNum) && acceptedNum < 0 || acceptedNum >= 100))
       {
           lstIntegers.Items.Add(txtInsert.Text);
           txtInsert.Clear();
           txtInsert.Focus();
           bubbleSort();

       }
       else
       {
          MessageBox.Show("Please input value between 1-100", "error", MessageBoxButtons.OK);
          txtInsert.Text = "";
       }
    }
    else
    {
       MessageBox.Show("Number already exists in list", "error", MessageBoxButtons.OK);
    }
  }
  else
  {
     MessageBox.Show("Please input value between 1-100", "error", MessageBoxButtons.OK);
  }
  if (lstIntegers.Items.Count == 30)
  {
      MessageBox.Show("Maximum number of entries exceeded", "error", MessageBoxButtons.OK);
      //button enabled was false however couldn't then add another 
      btnInsert.Enabled = true;
  }
}

Answer 1

You can use List.Sort to get the correct sort, no need for the bubbleSort method. You can use Enumerable.First , Last and simple math to get the first,last and middle values:

int acceptedNum;
bool validNumber = int.TryParse(txtInsert.Text, out acceptedNum);
if (!validNumber || acceptedNum < 1 || acceptedNum > 100)
{
    MessageBox.Show("Please input value between 1-100", "error", MessageBoxButtons.OK);
    return;
}

List<int> existingNumbers = lstIntegers.Items.Cast<Object>().Select(System.Convert.ToInt32).ToList();
if (existingNumbers.Contains(acceptedNum))
{
    MessageBox.Show("Number already exists in list", "error", MessageBoxButtons.OK);
    return;
}

existingNumbers.Add(acceptedNum);
existingNumbers.Sort(); // Quicksort with 30 items

int firstValue = existingNumbers.First();
int lastValue = existingNumbers.Last();
int middleValue = existingNumbers[existingNumbers.Count / 2];

int count = lstIntegers.Items.Count;
int maxNumbers = 30;
if (count == maxNumbers)
{
   MessageBox.Show("Maximum number of entries exceeded", "error", MessageBoxButtons.OK);
   btnInsert.Enabled = false;
}

lstIntegers.Items.Clear();
lstIntegers.Items.AddRange(existingNumbers.Cast<object>().ToArray());

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