title: System.FormatException: Input string was not in a correct format
body: <pre><code>    private void ReadUnitPrice()
      {
          Console.Write("Enter the unit gross price: ");
          unitPrice = double.Parse(Console.ReadLine());
      }
  </code></pre>
  
  <p>This should work, but I'm missing something obvious. Whenever I input a double it gives me the error: System.FormatException: Input string was not in a correct format.
  Note that 'unitPrice' is declared as a double.</p>