Invariant culture is always the same, regardless of the computer's settings:
using System;
using System.Text;
using System.Globalization;
class Sample
{
public static void Main()
{
DateTime dt = new DateTime(2000, 1, 2);
CultureInfo iv = CultureInfo.InvariantCulture;
Console.WriteLine(dt.ToString(iv));
Console.WriteLine(dt.ToString("d", iv));
}
}
The output:
01/02/2000 00:00:00
01/02/2000