Sum up Double ReadLine values?
<p>I'm new to C# programming and I'm not sure what I'm doing wrong because I can't sum up numbers that are Double. If I input 2,5 and 2,5 I get 5, but if I enter 2.5 and 2.5 I get zero when I use a dot instead of a comma between the numbers. Why this?</p>

<p>I add some of my code:</p>

<pre><code> private void ReadInputAndSumNumbers()
    {
        while (!done)
        {
            Console.Write("Number: ");
            if (double.TryParse(Console.ReadLine(), out num))
            {
                if (num == 0)
                {
                    done = true;
                }
                else
                {
                    sum += num;
                }
            }
        }
    }
</code></pre>

<p>My settings are to use a comma, but I would like the user to be able to enter a value with dot also</p>
