public static string ToTimeOffsetString(this TimeSpan offset, string seperator = "")
{
var hours = Math.Abs(offset.Hours).ToString(CultureInfo.InvariantCulture);
var minutes = Math.Abs(offset.Minutes).ToString(CultureInfo.InvariantCulture);
return (offset < TimeSpan.Zero ? "-" : "+")
+ (hours.Length == 1 ? "0" + hours : hours)
+ seperator
+ (minutes.Length == 1 ? "0" + minutes : minutes);
}