public static TimeZoneStructure FromTimeZoneInfo(TimeZoneInfo staticTimeZone)
{
TimeZoneInfo.AdjustmentRule[] rules = staticTimeZone.GetAdjustmentRules();
if (rules.Length > 1)
{
throw new ArgumentException("Cannot create TimeZoneStructure from a time zone with multiple DST rules");
}
TimeZoneStructure structure = new TimeZoneStructure();
if (rules.Length == 0)
{
// no daylight saving
structure.SetBias(staticTimeZone.BaseUtcOffset, new TimeSpan());
structure.stStandardDate = new SystemTime();
structure.stDaylightDate = new SystemTime();
}
else
{
TimeZoneInfo.AdjustmentRule rule = rules[0];
structure.SetBias(staticTimeZone.BaseUtcOffset, rule.DaylightDelta);
structure.stStandardDate = AdjustmentRuleHelper.GetStandardDate(rule);
structure.stDaylightDate = AdjustmentRuleHelper.GetDaylightDate(rule);
}
return(structure);
}
/// Note about how Outlook selects the effective adjustment rule:
/// For backward compatibility reasons, the effective rule is always the static timezone
/// rule used by the OS.
/// It's possible however that there is no dynamic rule that matches the static rule,
/// If that's the case, Outlook will replace the dynamic rule of the current year
/// with the static rule, which will be marked as the effective rule.
/// <param name="effectiveRule">null if there are no daylight savings</param>
public static TimeZoneDefinitionStructure FromTimeZoneInfo(TimeZoneInfo timezone, TimeZoneInfo.AdjustmentRule effectiveRule, int effectiveRuleYear, bool isRecurringTimeZoneRule)
{
TimeZoneInfo.AdjustmentRule[] adjustmentRules = timezone.GetAdjustmentRules();
if (effectiveRule != null)
{
if ((effectiveRule.DaylightTransitionStart.IsFixedDateRule || effectiveRule.DaylightTransitionEnd.IsFixedDateRule) &&
effectiveRule.DateStart.Year < effectiveRule.DateEnd.Year)
{
// a rule can either be fixed-date (wYear is not zero) or floating-date (wYear is zero)
// a fixed-date rule cannot span multiple years.
throw new NotImplementedException("Effective DST rule cannot be fixed-date and span multiple years");
}
if (adjustmentRules.Length == 0)
{
// effective rule != null means timezone rule is defined, but the timezone has no such rule
throw new ArgumentException("Time zone does not match effective rule");
}
}
TimeZoneRuleFlags effectiveRuleFlags = TimeZoneRuleFlags.EffectiveTimeZoneRule;
if (isRecurringTimeZoneRule)
{
effectiveRuleFlags |= TimeZoneRuleFlags.RecurringTimeZoneRule;
}
TimeZoneRuleStructure[] tzRules;
if (adjustmentRules.Length == 0)
{
// at this point effectiveRule must be null
TimeZoneRuleStructure ruleStructure = new TimeZoneRuleStructure();
ruleStructure.SetBias(timezone.BaseUtcOffset, new TimeSpan());
ruleStructure.wYear = 1601; // That's what Outlook 2007 SP3 uses
ruleStructure.TZRuleFlags = effectiveRuleFlags;
tzRules = new TimeZoneRuleStructure[] { ruleStructure };
}
else
{
List <TimeZoneRuleStructure> rules = new List <TimeZoneRuleStructure>();
// First we will create a list of the dynamic rules:
// we have an effective rule and at least one dynamic rule
int firstRuleYear = adjustmentRules[0].DateStart.Year;
if (firstRuleYear > 1)
{
TimeZoneRuleStructure firstRule = new TimeZoneRuleStructure();
firstRule.SetBias(timezone.BaseUtcOffset, adjustmentRules[0].DaylightDelta);
firstRule.wYear = (ushort)(firstRuleYear - 1);
rules.Add(firstRule);
}
for (int index = 0; index < adjustmentRules.Length; index++)
{
TimeZoneInfo.AdjustmentRule adjustmentRule = adjustmentRules[index];
TimeZoneRuleStructure rule = new TimeZoneRuleStructure();
rule.wYear = (ushort)adjustmentRule.DateStart.Year;;
rule.SetBias(timezone.BaseUtcOffset, adjustmentRule.DaylightDelta);
rule.stStandardDate = AdjustmentRuleHelper.GetStandardDate(adjustmentRule);
rule.stDaylightDate = AdjustmentRuleHelper.GetDaylightDate(adjustmentRule);
rules.Add(rule);
}
int lastRuleYear = adjustmentRules[adjustmentRules.Length - 1].DateEnd.Year;
if (lastRuleYear < 9999)
{
TimeZoneRuleStructure lastRule = new TimeZoneRuleStructure();
lastRule.SetBias(timezone.BaseUtcOffset, adjustmentRules[adjustmentRules.Length - 1].DaylightDelta);
lastRule.wYear = (ushort)(lastRuleYear + 1);
rules.Add(lastRule);
}
// Outlook will try to find a rule that match the static rule, and will use the last rule that fits
// now we will replace a dynamic rule with the appropriate static rule
// find the index for the rule
int effectiveRuleIndex = 0;
for (int index = 0; index < rules.Count; index++)
{
if (effectiveRuleYear >= rules[index].wYear)
{
effectiveRuleIndex = index;
}
}
// prepare the effective rule structure
TimeZoneRuleStructure ruleStructure = new TimeZoneRuleStructure();
ruleStructure.wYear = rules[effectiveRuleIndex].wYear;
ruleStructure.TZRuleFlags = effectiveRuleFlags;
if (effectiveRule == null)
{
// We should have a no-daylight-savings rule
ruleStructure.SetBias(timezone.BaseUtcOffset, new TimeSpan());
}
else
{
ruleStructure.SetBias(timezone.BaseUtcOffset, effectiveRule.DaylightDelta);
ruleStructure.stStandardDate = AdjustmentRuleHelper.GetStandardDate(effectiveRule);
ruleStructure.stDaylightDate = AdjustmentRuleHelper.GetDaylightDate(effectiveRule);
}
rules[effectiveRuleIndex] = ruleStructure;
tzRules = rules.ToArray();
}
TimeZoneDefinitionStructure structure = new TimeZoneDefinitionStructure();
structure.KeyName = timezone.Id;
structure.TZRules = tzRules;
return(structure);
}