Q:

displaying the factors of a number

I'm trying to get all the factors of a number provided by a user and after a button click displaying all the factors on a MessageBox. 
This is what my code code taken from Getting Factors of a Number answer by Mark Byers looks like, I thought I was pretty close, but I'm displaying the number of factors not the actual factor numbers. 
For example if the user types in 10 and uses a button click, the MessageBox displays the number 4, but i'm wanting it to display the actual factors of 10 which should be 1,2,5,10.
*how can I display the factors?
public int Divisors(int fact)
    {
        int number = int.Parse(textBox2.Text);
        int factorCount = 0;
        int sqrt = (int)Math.Ceiling(Math.Sqrt(number));

        for (int i = 1; i < sqrt; i++)
        {
            if (number % i == 0)
            {
                factorCount += 2; //  We found a pair of factors.
            }
        }

        // Check if our number is an exact square.
        if (sqrt * sqrt == number)
        {
            factorCount++;
        }

        return factorCount;
    }

private void ShowallButton_Click(object sender, EventArgs e)
    {
        int input = int.Parse(textBox2.Text);
        double output = Divisors(input);

        MessageBox.Show(+output + "");
    }

A:

        public List<int> Divisors(int fact)
    {
        List<int> factors = new List<int>();
        int number = int.Parse(textBox2.Text);
        int factorCount = 0;
        int sqrt = (int)Math.Ceiling(Math.Sqrt(number));

        for (int i = 1; i < sqrt; i++)
        {
            if (number % i == 0)
            {
                factors.Add(i);
                factorCount += 2; //  We found a pair of factors.
            }
        }

        // Check if our number is an exact square.
        if (sqrt * sqrt == number)
        {
            factorCount++;
        }

        // return factorCount;
        return factors;
    }
    private void ShowallButton_Click(object sender, EventArgs e)
    {
        int input = int.Parse(textBox2.Text);
        List<int> factors = Divisors(input);
        string message = $"The Divisors are {string.Join(",", factors)}";
        MessageBox.Show(message);
    }

