public static TimeZoneInfo FindSystemTimeZoneById(string id)
{
if (id == null)
{
throw new ArgumentNullException(nameof(id));
}
if (id.Length == 0 || id.Length > 255 || id.Contains("\0"))
{
throw new ArgumentException(String.Format(SR.Argument_TimeZoneNotFound, id));
}
//
// Check first the Utc Ids and return the cached one because in GetCorrespondingKind
// we use reference equality
//
if (id.Equals(TimeZoneInfo.Utc.Id, StringComparison.OrdinalIgnoreCase))
{
return(TimeZoneInfo.Utc);
}
TimeZoneInfo value;
CachedData cache = s_cachedData;
// Use the current cache if it exists
if (cache._systemTimeZones != null)
{
if (cache._systemTimeZones.TryGetValue(id, out value))
{
return(value);
}
}
// See if the cache was fully filled, if not, fill it then check again.
if (!cache.AreSystemTimesEnumerated)
{
cache.EnumerateSystemTimes();
if (cache._systemTimeZones.TryGetValue(id, out value))
{
return(value);
}
}
throw new ArgumentException(String.Format(SR.Argument_TimeZoneNotFound, id));
}