Move TimeZoneInfo.Win32.cs to shared CoreLib partition (#15953)

Reconcile deltas with CoreRT and refactor interop to follow coding conventions

Signed-off-by: dotnet-bot-corefx-mirror <dotnet-bot@microsoft.com>

5 files changed, 1146 insertions, 0 deletions

diff --git a/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.MUI.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.MUI.cs
new file mode 100644
index 0000000000..6ed7aa2dc4
--- /dev/null
+++ b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.MUI.cs
@@ -0,0 +1,18 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+using System.Text;
+
+internal static partial class Interop
+{
+    internal static partial class Kernel32
+    {
+        internal const uint MUI_PREFERRED_UI_LANGUAGES = 0x10;
+
+        [DllImport(Libraries.Kernel32, CharSet = CharSet.Unicode, SetLastError = true, ExactSpelling = true)]
+        internal static extern bool GetFileMUIPath(uint flags, String filePath, [Out] StringBuilder language, ref int languageLength, [Out] StringBuilder fileMuiPath, ref int fileMuiPathLength, ref Int64 enumerator);
+    }
+}
diff --git a/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.TimeZone.Registry.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.TimeZone.Registry.cs
new file mode 100644
index 0000000000..062d1caeba
--- /dev/null
+++ b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.TimeZone.Registry.cs
@@ -0,0 +1,31 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+internal static partial class Interop
+{
+    internal static partial class Kernel32
+    {
+        [StructLayout(LayoutKind.Sequential)]
+        internal struct REG_TZI_FORMAT
+        {
+            internal int Bias;
+            internal int StandardBias;
+            internal int DaylightBias;
+            internal SYSTEMTIME StandardDate;
+            internal SYSTEMTIME DaylightDate;
+
+            internal REG_TZI_FORMAT(in TIME_ZONE_INFORMATION tzi)
+            {
+                Bias = tzi.Bias;
+                StandardDate = tzi.StandardDate;
+                StandardBias = tzi.StandardBias;
+                DaylightDate = tzi.DaylightDate;
+                DaylightBias = tzi.DaylightBias;
+            }
+        }
+    }
+}
diff --git a/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.TimeZone.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.TimeZone.cs
new file mode 100644
index 0000000000..05f13ac8ed
--- /dev/null
+++ b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.TimeZone.cs
@@ -0,0 +1,94 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+internal static partial class Interop
+{
+    internal static partial class Kernel32
+    {
+        internal struct SYSTEMTIME
+        {
+            internal ushort Year;
+            internal ushort Month;
+            internal ushort DayOfWeek;
+            internal ushort Day;
+            internal ushort Hour;
+            internal ushort Minute;
+            internal ushort Second;
+            internal ushort Milliseconds;
+
+            internal bool Equals(in SYSTEMTIME other) =>
+                    Year == other.Year &&
+                    Month == other.Month &&
+                    DayOfWeek == other.DayOfWeek &&
+                    Day == other.Day &&
+                    Hour == other.Hour &&
+                    Minute == other.Minute &&
+                    Second == other.Second &&
+                    Milliseconds == other.Milliseconds;
+        }
+
+        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+        internal unsafe struct TIME_DYNAMIC_ZONE_INFORMATION
+        {
+            internal int Bias;
+            internal fixed char StandardName[32];
+            internal SYSTEMTIME StandardDate;
+            internal int StandardBias;
+            internal fixed char DaylightName[32];
+            internal SYSTEMTIME DaylightDate;
+            internal int DaylightBias;
+            internal fixed char TimeZoneKeyName[128];
+            internal byte DynamicDaylightTimeDisabled;
+
+            internal string GetTimeZoneKeyName()
+            {
+                fixed (char* p = TimeZoneKeyName)
+                    return new string(p);
+            }
+        }
+
+        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+        internal unsafe struct TIME_ZONE_INFORMATION
+        {
+            internal int Bias;
+            internal fixed char StandardName[32];
+            internal SYSTEMTIME StandardDate;
+            internal int StandardBias;
+            internal fixed char DaylightName[32];
+            internal SYSTEMTIME DaylightDate;
+            internal int DaylightBias;
+
+            internal TIME_ZONE_INFORMATION(in TIME_DYNAMIC_ZONE_INFORMATION dtzi)
+            {
+                // The start of TIME_DYNAMIC_ZONE_INFORMATION has identical layout as TIME_ZONE_INFORMATION
+                fixed (TIME_ZONE_INFORMATION* pTo = &this)
+                fixed (TIME_DYNAMIC_ZONE_INFORMATION* pFrom = &dtzi)
+                    *pTo = *(TIME_ZONE_INFORMATION*)pFrom;
+            }
+
+            internal string GetStandardName()
+            {
+                fixed (char* p = StandardName)
+                    return new string(p);
+            }
+
+            internal string GetDaylightName()
+            {
+                fixed (char* p = DaylightName)
+                    return new string(p);
+            }
+        }
+
+        internal const uint TIME_ZONE_ID_INVALID = unchecked((uint)-1);
+
+        [DllImport(Libraries.Kernel32, CharSet = CharSet.Unicode, SetLastError = true, ExactSpelling = true)]
+        internal extern static uint GetDynamicTimeZoneInformation(out TIME_DYNAMIC_ZONE_INFORMATION pTimeZoneInformation);
+
+        [DllImport(Libraries.Kernel32, CharSet = CharSet.Unicode, SetLastError = true, ExactSpelling = true)]
+        internal static extern uint GetTimeZoneInformation(out TIME_ZONE_INFORMATION lpTimeZoneInformation);
+    }
+}
diff --git a/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems b/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems
index e49edfd367..c771f7b7be 100644
--- a/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems
+++ b/src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems
@@ -657,6 +657,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.WriteFile_SafeHandle_NativeOverlapped.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Normaliz\Interop.Idna.cs" Condition="'$(EnableDummyGlobalizationImplementation)' != 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Normaliz\Interop.Normalization.cs" Condition="'$(EnableDummyGlobalizationImplementation)' != 'true'" />
+    <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.TimeZone.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\OleAut32\Interop.SysAllocStringLen.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\OleAut32\Interop.SysFreeString.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\OleAut32\Interop.SysStringLen.cs" />
@@ -682,10 +683,13 @@
   </ItemGroup>
   <ItemGroup Condition="$(TargetsWindows) and '$(EnableWinRT)' != 'true'">
     <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStream.Win32.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\TimeZoneInfo.Win32.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Microsoft\Win32\SafeHandles\SafeLibraryHandle.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.LoadLibraryEx.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.FreeLibrary.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.CreateFile.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.MUI.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\Kernel32\Interop.TimeZone.Registry.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\User32\Interop.Constants.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\User32\Interop.SendMessageTimeout.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Interop\Windows\User32\Interop.LoadString.cs" />
diff --git a/src/Common/src/CoreLib/System/TimeZoneInfo.Win32.cs b/src/Common/src/CoreLib/System/TimeZoneInfo.Win32.cs
new file mode 100644
index 0000000000..5950c9565a
--- /dev/null
+++ b/src/Common/src/CoreLib/System/TimeZoneInfo.Win32.cs
@@ -0,0 +1,999 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Globalization;
+using System.IO;
+using System.Security;
+using System.Text;
+using System.Threading;
+
+using Microsoft.Win32;
+using Microsoft.Win32.SafeHandles;
+
+using Internal.Runtime.CompilerServices;
+
+using REG_TZI_FORMAT = Interop.Kernel32.REG_TZI_FORMAT;
+using TIME_ZONE_INFORMATION = Interop.Kernel32.TIME_ZONE_INFORMATION;
+using TIME_DYNAMIC_ZONE_INFORMATION = Interop.Kernel32.TIME_DYNAMIC_ZONE_INFORMATION;
+
+namespace System
+{
+    public sealed partial class TimeZoneInfo
+    {
+        // registry constants for the 'Time Zones' hive
+        //
+        private const string TimeZonesRegistryHive = @"SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones";
+        private const string DisplayValue = "Display";
+        private const string DaylightValue = "Dlt";
+        private const string StandardValue = "Std";
+        private const string MuiDisplayValue = "MUI_Display";
+        private const string MuiDaylightValue = "MUI_Dlt";
+        private const string MuiStandardValue = "MUI_Std";
+        private const string TimeZoneInfoValue = "TZI";
+        private const string FirstEntryValue = "FirstEntry";
+        private const string LastEntryValue = "LastEntry";
+
+        private const int MaxKeyLength = 255;
+
+#pragma warning disable 0420
+        private sealed partial class CachedData
+        {
+            private static TimeZoneInfo GetCurrentOneYearLocal()
+            {
+                // load the data from the OS
+                TIME_ZONE_INFORMATION timeZoneInformation;
+                uint result = Interop.Kernel32.GetTimeZoneInformation(out timeZoneInformation);
+                return result == Interop.Kernel32.TIME_ZONE_ID_INVALID ?
+                    CreateCustomTimeZone(LocalId, TimeSpan.Zero, LocalId, LocalId) :
+                    GetLocalTimeZoneFromWin32Data(timeZoneInformation, dstDisabled: false);
+            }
+
+            private volatile OffsetAndRule _oneYearLocalFromUtc;
+
+            public OffsetAndRule GetOneYearLocalFromUtc(int year)
+            {
+                OffsetAndRule oneYearLocFromUtc = _oneYearLocalFromUtc;
+                if (oneYearLocFromUtc == null || oneYearLocFromUtc.Year != year)
+                {
+                    TimeZoneInfo currentYear = GetCurrentOneYearLocal();
+                    AdjustmentRule rule = currentYear._adjustmentRules == null ? null : currentYear._adjustmentRules[0];
+                    oneYearLocFromUtc = new OffsetAndRule(year, currentYear.BaseUtcOffset, rule);
+                    _oneYearLocalFromUtc = oneYearLocFromUtc;
+                }
+                return oneYearLocFromUtc;
+            }
+        }
+#pragma warning restore 0420
+
+        private sealed class OffsetAndRule
+        {
+            public readonly int Year;
+            public readonly TimeSpan Offset;
+            public readonly AdjustmentRule Rule;
+
+            public OffsetAndRule(int year, TimeSpan offset, AdjustmentRule rule)
+            {
+                Year = year;
+                Offset = offset;
+                Rule = rule;
+            }
+        }
+
+        /// <summary>
+        /// Returns a cloned array of AdjustmentRule objects
+        /// </summary>
+        public AdjustmentRule[] GetAdjustmentRules()
+        {
+            if (_adjustmentRules == null)
+            {
+                return Array.Empty<AdjustmentRule>();
+            }
+
+            return (AdjustmentRule[])_adjustmentRules.Clone();
+        }
+
+        private static void PopulateAllSystemTimeZones(CachedData cachedData)
+        {
+            Debug.Assert(Monitor.IsEntered(cachedData));
+
+            using (RegistryKey reg = Registry.LocalMachine.OpenSubKey(TimeZonesRegistryHive, writable: false))
+            {
+                if (reg != null)
+                {
+                    foreach (string keyName in reg.GetSubKeyNames())
+                    {
+                        TimeZoneInfo value;
+                        Exception ex;
+                        TryGetTimeZone(keyName, false, out value, out ex, cachedData);  // populate the cache
+                    }
+                }
+            }
+        }
+
+        private TimeZoneInfo(in TIME_ZONE_INFORMATION zone, bool dstDisabled)
+        {
+            string standardName = zone.GetStandardName();
+            if (standardName.Length == 0)
+            {
+                _id = LocalId;  // the ID must contain at least 1 character - initialize _id to "Local"
+            }
+            else
+            {
+                _id = standardName;
+            }
+            _baseUtcOffset = new TimeSpan(0, -(zone.Bias), 0);
+
+            if (!dstDisabled)
+            {
+                // only create the adjustment rule if DST is enabled
+                REG_TZI_FORMAT regZone = new REG_TZI_FORMAT(zone);
+                AdjustmentRule rule = CreateAdjustmentRuleFromTimeZoneInformation(regZone, DateTime.MinValue.Date, DateTime.MaxValue.Date, zone.Bias);
+                if (rule != null)
+                {
+                    _adjustmentRules = new[] { rule };
+                }
+            }
+
+            ValidateTimeZoneInfo(_id, _baseUtcOffset, _adjustmentRules, out _supportsDaylightSavingTime);
+            _displayName = standardName;
+            _standardDisplayName = standardName;
+            _daylightDisplayName = zone.GetDaylightName();
+        }
+
+        /// <summary>
+        /// Helper function to check if the current TimeZoneInformation struct does not support DST.
+        /// This check returns true when the DaylightDate == StandardDate.
+        /// This check is only meant to be used for "Local".
+        /// </summary>
+        private static bool CheckDaylightSavingTimeNotSupported(in TIME_ZONE_INFORMATION timeZone) =>
+            timeZone.DaylightDate.Equals(timeZone.StandardDate);
+
+        /// <summary>
+        /// Converts a REG_TZI_FORMAT struct to an AdjustmentRule.
+        /// </summary>
+        private static AdjustmentRule CreateAdjustmentRuleFromTimeZoneInformation(in REG_TZI_FORMAT timeZoneInformation, DateTime startDate, DateTime endDate, int defaultBaseUtcOffset)
+        {
+            bool supportsDst = timeZoneInformation.StandardDate.Month != 0;
+
+            if (!supportsDst)
+            {
+                if (timeZoneInformation.Bias == defaultBaseUtcOffset)
+                {
+                    // this rule will not contain any information to be used to adjust dates. just ignore it
+                    return null;
+                }
+
+                return AdjustmentRule.CreateAdjustmentRule(
+                    startDate,
+                    endDate,
+                    TimeSpan.Zero, // no daylight saving transition
+                    TransitionTime.CreateFixedDateRule(DateTime.MinValue, 1, 1),
+                    TransitionTime.CreateFixedDateRule(DateTime.MinValue.AddMilliseconds(1), 1, 1),
+                    new TimeSpan(0, defaultBaseUtcOffset - timeZoneInformation.Bias, 0),  // Bias delta is all what we need from this rule
+                    noDaylightTransitions: false);
+            }
+
+            //
+            // Create an AdjustmentRule with TransitionTime objects
+            //
+            TransitionTime daylightTransitionStart;
+            if (!TransitionTimeFromTimeZoneInformation(timeZoneInformation, out daylightTransitionStart, readStartDate: true))
+            {
+                return null;
+            }
+
+            TransitionTime daylightTransitionEnd;
+            if (!TransitionTimeFromTimeZoneInformation(timeZoneInformation, out daylightTransitionEnd, readStartDate: false))
+            {
+                return null;
+            }
+
+            if (daylightTransitionStart.Equals(daylightTransitionEnd))
+            {
+                // this happens when the time zone does support DST but the OS has DST disabled
+                return null;
+            }
+
+            return AdjustmentRule.CreateAdjustmentRule(
+                startDate,
+                endDate,
+                new TimeSpan(0, -timeZoneInformation.DaylightBias, 0),
+                daylightTransitionStart,
+                daylightTransitionEnd,
+                new TimeSpan(0, defaultBaseUtcOffset - timeZoneInformation.Bias, 0),
+                noDaylightTransitions: false);
+        }
+
+        /// <summary>
+        /// Helper function that searches the registry for a time zone entry
+        /// that matches the TimeZoneInformation struct.
+        /// </summary>
+        private static string FindIdFromTimeZoneInformation(in TIME_ZONE_INFORMATION timeZone, out bool dstDisabled)
+        {
+            dstDisabled = false;
+
+            using (RegistryKey key = Registry.LocalMachine.OpenSubKey(TimeZonesRegistryHive, writable: false))
+            {
+                if (key == null)
+                {
+                    return null;
+                }
+
+                foreach (string keyName in key.GetSubKeyNames())
+                {
+                    if (TryCompareTimeZoneInformationToRegistry(timeZone, keyName, out dstDisabled))
+                    {
+                        return keyName;
+                    }
+                }
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Helper function for retrieving the local system time zone.
+        /// May throw COMException, TimeZoneNotFoundException, InvalidTimeZoneException.
+        /// Assumes cachedData lock is taken.
+        /// </summary>
+        /// <returns>A new TimeZoneInfo instance.</returns>
+        private static TimeZoneInfo GetLocalTimeZone(CachedData cachedData)
+        {
+            Debug.Assert(Monitor.IsEntered(cachedData));
+
+            //
+            // Try using the "kernel32!GetDynamicTimeZoneInformation" API to get the "id"
+            //
+            var dynamicTimeZoneInformation = new TIME_DYNAMIC_ZONE_INFORMATION();
+
+            // call kernel32!GetDynamicTimeZoneInformation...
+            uint result = Interop.Kernel32.GetDynamicTimeZoneInformation(out dynamicTimeZoneInformation);
+            if (result == Interop.Kernel32.TIME_ZONE_ID_INVALID)
+            {
+                // return a dummy entry
+                return CreateCustomTimeZone(LocalId, TimeSpan.Zero, LocalId, LocalId);
+            }
+
+            // check to see if we can use the key name returned from the API call
+            string dynamicTimeZoneKeyName = dynamicTimeZoneInformation.GetTimeZoneKeyName();
+            if (dynamicTimeZoneKeyName.Length != 0)
+            {
+                TimeZoneInfo zone;
+                Exception ex;
+
+                if (TryGetTimeZone(dynamicTimeZoneKeyName, dynamicTimeZoneInformation.DynamicDaylightTimeDisabled != 0, out zone, out ex, cachedData) == TimeZoneInfoResult.Success)
+                {
+                    // successfully loaded the time zone from the registry
+                    return zone;
+                }
+            }
+
+            var timeZoneInformation = new TIME_ZONE_INFORMATION(dynamicTimeZoneInformation);
+
+            // the key name was not returned or it pointed to a bogus entry - search for the entry ourselves
+            string id = FindIdFromTimeZoneInformation(timeZoneInformation, out bool dstDisabled);
+
+            if (id != null)
+            {
+                TimeZoneInfo zone;
+                Exception ex;
+                if (TryGetTimeZone(id, dstDisabled, out zone, out ex, cachedData) == TimeZoneInfoResult.Success)
+                {
+                    // successfully loaded the time zone from the registry
+                    return zone;
+                }
+            }
+
+            // We could not find the data in the registry.  Fall back to using
+            // the data from the Win32 API
+            return GetLocalTimeZoneFromWin32Data(timeZoneInformation, dstDisabled);
+        }
+
+        /// <summary>
+        /// Helper function used by 'GetLocalTimeZone()' - this function wraps a bunch of
+        /// try/catch logic for handling the TimeZoneInfo private constructor that takes
+        /// a TIME_ZONE_INFORMATION structure.
+        /// </summary>
+        private static TimeZoneInfo GetLocalTimeZoneFromWin32Data(in TIME_ZONE_INFORMATION timeZoneInformation, bool dstDisabled)
+        {
+            // first try to create the TimeZoneInfo with the original 'dstDisabled' flag
+            try
+            {
+                return new TimeZoneInfo(timeZoneInformation, dstDisabled);
+            }
+            catch (ArgumentException) { }
+            catch (InvalidTimeZoneException) { }
+
+            // if 'dstDisabled' was false then try passing in 'true' as a last ditch effort
+            if (!dstDisabled)
+            {
+                try
+                {
+                    return new TimeZoneInfo(timeZoneInformation, dstDisabled: true);
+                }
+                catch (ArgumentException) { }
+                catch (InvalidTimeZoneException) { }
+            }
+
+            // the data returned from Windows is completely bogus; return a dummy entry
+            return CreateCustomTimeZone(LocalId, TimeSpan.Zero, LocalId, LocalId);
+        }
+
+        /// <summary>
+        /// Helper function for retrieving a TimeZoneInfo object by <time_zone_name>.
+        /// This function wraps the logic necessary to keep the private
+        /// SystemTimeZones cache in working order
+        ///
+        /// This function will either return a valid TimeZoneInfo instance or
+        /// it will throw 'InvalidTimeZoneException' / 'TimeZoneNotFoundException'.
+        /// </summary>
+        public static TimeZoneInfo FindSystemTimeZoneById(string id)
+        {
+            // Special case for Utc as it will not exist in the dictionary with the rest
+            // of the system time zones.  There is no need to do this check for Local.Id
+            // since Local is a real time zone that exists in the dictionary cache
+            if (string.Equals(id, UtcId, StringComparison.OrdinalIgnoreCase))
+            {
+                return Utc;
+            }
+
+            if (id == null)
+            {
+                throw new ArgumentNullException(nameof(id));
+            }
+            if (id.Length == 0 || id.Length > MaxKeyLength || id.Contains('\0'))
+            {
+                throw new TimeZoneNotFoundException(SR.Format(SR.TimeZoneNotFound_MissingData, id));
+            }
+
+            TimeZoneInfo value;
+            Exception e;
+
+            TimeZoneInfoResult result;
+
+            CachedData cachedData = s_cachedData;
+
+            lock (cachedData)
+            {
+                result = TryGetTimeZone(id, false, out value, out e, cachedData);
+            }
+
+            if (result == TimeZoneInfoResult.Success)
+            {
+                return value;
+            }
+            else if (result == TimeZoneInfoResult.InvalidTimeZoneException)
+            {
+                throw new InvalidTimeZoneException(SR.Format(SR.InvalidTimeZone_InvalidRegistryData, id), e);
+            }
+            else if (result == TimeZoneInfoResult.SecurityException)
+            {
+                throw new SecurityException(SR.Format(SR.Security_CannotReadRegistryData, id), e);
+            }
+            else
+            {
+                throw new TimeZoneNotFoundException(SR.Format(SR.TimeZoneNotFound_MissingData, id), e);
+            }
+        }
+
+        // DateTime.Now fast path that avoids allocating an historically accurate TimeZoneInfo.Local and just creates a 1-year (current year) accurate time zone
+        internal static TimeSpan GetDateTimeNowUtcOffsetFromUtc(DateTime time, out bool isAmbiguousLocalDst)
+        {
+            bool isDaylightSavings = false;
+            isAmbiguousLocalDst = false;
+            TimeSpan baseOffset;
+            int timeYear = time.Year;
+
+            OffsetAndRule match = s_cachedData.GetOneYearLocalFromUtc(timeYear);
+            baseOffset = match.Offset;
+
+            if (match.Rule != null)
+            {
+                baseOffset = baseOffset + match.Rule.BaseUtcOffsetDelta;
+                if (match.Rule.HasDaylightSaving)
+                {
+                    isDaylightSavings = GetIsDaylightSavingsFromUtc(time, timeYear, match.Offset, match.Rule, null, out isAmbiguousLocalDst, Local);
+                    baseOffset += (isDaylightSavings ? match.Rule.DaylightDelta : TimeSpan.Zero /* FUTURE: rule.StandardDelta */);
+                }
+            }
+            return baseOffset;
+        }
+
+        /// <summary>
+        /// Converts a REG_TZI_FORMAT struct to a TransitionTime
+        /// - When the argument 'readStart' is true the corresponding daylightTransitionTimeStart field is read
+        /// - When the argument 'readStart' is false the corresponding dayightTransitionTimeEnd field is read
+        /// </summary>
+        private static bool TransitionTimeFromTimeZoneInformation(in REG_TZI_FORMAT timeZoneInformation, out TransitionTime transitionTime, bool readStartDate)
+        {
+            //
+            // SYSTEMTIME -
+            //
+            // If the time zone does not support daylight saving time or if the caller needs
+            // to disable daylight saving time, the wMonth member in the SYSTEMTIME structure
+            // must be zero. If this date is specified, the DaylightDate value in the
+            // TIME_ZONE_INFORMATION structure must also be specified. Otherwise, the system
+            // assumes the time zone data is invalid and no changes will be applied.
+            //
+            bool supportsDst = (timeZoneInformation.StandardDate.Month != 0);
+
+            if (!supportsDst)
+            {
+                transitionTime = default(TransitionTime);
+                return false;
+            }
+
+            //
+            // SYSTEMTIME -
+            //
+            // * FixedDateRule -
+            //   If the Year member is not zero, the transition date is absolute; it will only occur one time
+            //
+            // * FloatingDateRule -
+            //   To select the correct day in the month, set the Year member to zero, the Hour and Minute
+            //   members to the transition time, the DayOfWeek member to the appropriate weekday, and the
+            //   Day member to indicate the occurence of the day of the week within the month (first through fifth).
+            //
+            //   Using this notation, specify the 2:00a.m. on the first Sunday in April as follows:
+            //   Hour      = 2,
+            //   Month     = 4,
+            //   DayOfWeek = 0,
+            //   Day       = 1.
+            //
+            //   Specify 2:00a.m. on the last Thursday in October as follows:
+            //   Hour      = 2,
+            //   Month     = 10,
+            //   DayOfWeek = 4,
+            //   Day       = 5.
+            //
+            if (readStartDate)
+            {
+                //
+                // read the "daylightTransitionStart"
+                //
+                if (timeZoneInformation.DaylightDate.Year == 0)
+                {
+                    transitionTime = TransitionTime.CreateFloatingDateRule(
+                                     new DateTime(1,    /* year  */
+                                                  1,    /* month */
+                                                  1,    /* day   */
+                                                  timeZoneInformation.DaylightDate.Hour,
+                                                  timeZoneInformation.DaylightDate.Minute,
+                                                  timeZoneInformation.DaylightDate.Second,
+                                                  timeZoneInformation.DaylightDate.Milliseconds),
+                                     timeZoneInformation.DaylightDate.Month,
+                                     timeZoneInformation.DaylightDate.Day,   /* Week 1-5 */
+                                     (DayOfWeek)timeZoneInformation.DaylightDate.DayOfWeek);
+                }
+                else
+                {
+                    transitionTime = TransitionTime.CreateFixedDateRule(
+                                     new DateTime(1,    /* year  */
+                                                  1,    /* month */
+                                                  1,    /* day   */
+                                                  timeZoneInformation.DaylightDate.Hour,
+                                                  timeZoneInformation.DaylightDate.Minute,
+                                                  timeZoneInformation.DaylightDate.Second,
+                                                  timeZoneInformation.DaylightDate.Milliseconds),
+                                     timeZoneInformation.DaylightDate.Month,
+                                     timeZoneInformation.DaylightDate.Day);
+                }
+            }
+            else
+            {
+                //
+                // read the "daylightTransitionEnd"
+                //
+                if (timeZoneInformation.StandardDate.Year == 0)
+                {
+                    transitionTime = TransitionTime.CreateFloatingDateRule(
+                                     new DateTime(1,    /* year  */
+                                                  1,    /* month */
+                                                  1,    /* day   */
+                                                  timeZoneInformation.StandardDate.Hour,
+                                                  timeZoneInformation.StandardDate.Minute,
+                                                  timeZoneInformation.StandardDate.Second,
+                                                  timeZoneInformation.StandardDate.Milliseconds),
+                                     timeZoneInformation.StandardDate.Month,
+                                     timeZoneInformation.StandardDate.Day,   /* Week 1-5 */
+                                     (DayOfWeek)timeZoneInformation.StandardDate.DayOfWeek);
+                }
+                else
+                {
+                    transitionTime = TransitionTime.CreateFixedDateRule(
+                                     new DateTime(1,    /* year  */
+                                                  1,    /* month */
+                                                  1,    /* day   */
+                                                  timeZoneInformation.StandardDate.Hour,
+                                                  timeZoneInformation.StandardDate.Minute,
+                                                  timeZoneInformation.StandardDate.Second,
+                                                  timeZoneInformation.StandardDate.Milliseconds),
+                                     timeZoneInformation.StandardDate.Month,
+                                     timeZoneInformation.StandardDate.Day);
+                }
+            }
+
+            return true;
+        }
+
+        /// <summary>
+        /// Helper function that takes:
+        ///  1. A string representing a <time_zone_name> registry key name.
+        ///  2. A REG_TZI_FORMAT struct containing the default rule.
+        ///  3. An AdjustmentRule[] out-parameter.
+        /// </summary>
+        private static bool TryCreateAdjustmentRules(string id, in REG_TZI_FORMAT defaultTimeZoneInformation, out AdjustmentRule[] rules, out Exception e, int defaultBaseUtcOffset)
+        {
+            rules = null;
+            e = null;
+
+            try
+            {
+                // Optional, Dynamic Time Zone Registry Data
+                // -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
+                //
+                // HKLM
+                //     Software
+                //         Microsoft
+                //             Windows NT
+                //                 CurrentVersion
+                //                     Time Zones
+                //                         <time_zone_name>
+                //                             Dynamic DST
+                // * "FirstEntry" REG_DWORD "1980"
+                //                           First year in the table. If the current year is less than this value,
+                //                           this entry will be used for DST boundaries
+                // * "LastEntry"  REG_DWORD "2038"
+                //                           Last year in the table. If the current year is greater than this value,
+                //                           this entry will be used for DST boundaries"
+                // * "<year1>"    REG_BINARY REG_TZI_FORMAT
+                // * "<year2>"    REG_BINARY REG_TZI_FORMAT
+                // * "<year3>"    REG_BINARY REG_TZI_FORMAT
+                //
+                using (RegistryKey dynamicKey = Registry.LocalMachine.OpenSubKey(TimeZonesRegistryHive + "\\" + id + "\\Dynamic DST", writable: false))
+                {
+                    if (dynamicKey == null)
+                    {
+                        AdjustmentRule rule = CreateAdjustmentRuleFromTimeZoneInformation(
+                            defaultTimeZoneInformation, DateTime.MinValue.Date, DateTime.MaxValue.Date, defaultBaseUtcOffset);
+                        if (rule != null)
+                        {
+                            rules = new[] { rule };
+                        }
+                        return true;
+                    }
+
+                    //
+                    // loop over all of the "<time_zone_name>\Dynamic DST" hive entries
+                    //
+                    // read FirstEntry  {MinValue      - (year1, 12, 31)}
+                    // read MiddleEntry {(yearN, 1, 1) - (yearN, 12, 31)}
+                    // read LastEntry   {(yearN, 1, 1) - MaxValue       }
+
+                    // read the FirstEntry and LastEntry key values (ex: "1980", "2038")
+                    int first = (int)dynamicKey.GetValue(FirstEntryValue, -1, RegistryValueOptions.None);
+                    int last = (int)dynamicKey.GetValue(LastEntryValue, -1, RegistryValueOptions.None);
+
+                    if (first == -1 || last == -1 || first > last)
+                    {
+                        return false;
+                    }
+
+                    // read the first year entry
+                    REG_TZI_FORMAT dtzi;
+
+                    if (!TryGetTimeZoneEntryFromRegistry(dynamicKey, first.ToString(CultureInfo.InvariantCulture), out dtzi))
+                    {
+                        return false;
+                    }
+
+                    if (first == last)
+                    {
+                        // there is just 1 dynamic rule for this time zone.
+                        AdjustmentRule rule = CreateAdjustmentRuleFromTimeZoneInformation(dtzi, DateTime.MinValue.Date, DateTime.MaxValue.Date, defaultBaseUtcOffset);
+                        if (rule != null)
+                        {
+                            rules = new[] { rule };
+                        }
+                        return true;
+                    }
+
+                    List<AdjustmentRule> rulesList = new List<AdjustmentRule>(1);
+
+                    // there are more than 1 dynamic rules for this time zone.
+                    AdjustmentRule firstRule = CreateAdjustmentRuleFromTimeZoneInformation(
+                        dtzi,
+                        DateTime.MinValue.Date,        // MinValue
+                        new DateTime(first, 12, 31),   // December 31, <FirstYear>
+                        defaultBaseUtcOffset);
+
+                    if (firstRule != null)
+                    {
+                        rulesList.Add(firstRule);
+                    }
+
+                    // read the middle year entries
+                    for (int i = first + 1; i < last; i++)
+                    {
+                        if (!TryGetTimeZoneEntryFromRegistry(dynamicKey, i.ToString(CultureInfo.InvariantCulture), out dtzi))
+                        {
+                            return false;
+                        }
+                        AdjustmentRule middleRule = CreateAdjustmentRuleFromTimeZoneInformation(
+                            dtzi,
+                            new DateTime(i, 1, 1),    // January  01, <Year>
+                            new DateTime(i, 12, 31),  // December 31, <Year>
+                            defaultBaseUtcOffset);
+
+                        if (middleRule != null)
+                        {
+                            rulesList.Add(middleRule);
+                        }
+                    }
+
+                    // read the last year entry
+                    if (!TryGetTimeZoneEntryFromRegistry(dynamicKey, last.ToString(CultureInfo.InvariantCulture), out dtzi))
+                    {
+                        return false;
+                    }
+                    AdjustmentRule lastRule = CreateAdjustmentRuleFromTimeZoneInformation(
+                        dtzi,
+                        new DateTime(last, 1, 1),    // January  01, <LastYear>
+                        DateTime.MaxValue.Date,      // MaxValue
+                        defaultBaseUtcOffset);
+
+                    if (lastRule != null)
+                    {
+                        rulesList.Add(lastRule);
+                    }
+
+                    // convert the List to an AdjustmentRule array
+                    if (rulesList.Count != 0)
+                    {
+                        rules = rulesList.ToArray();
+                    }
+                } // end of: using (RegistryKey dynamicKey...
+            }
+            catch (InvalidCastException ex)
+            {
+                // one of the RegistryKey.GetValue calls could not be cast to an expected value type
+                e = ex;
+                return false;
+            }
+            catch (ArgumentOutOfRangeException ex)
+            {
+                e = ex;
+                return false;
+            }
+            catch (ArgumentException ex)
+            {
+                e = ex;
+                return false;
+            }
+            return true;
+        }
+
+        private unsafe static bool TryGetTimeZoneEntryFromRegistry(RegistryKey key, string name, out REG_TZI_FORMAT dtzi)
+        {
+            byte[] regValue = key.GetValue(name, null, RegistryValueOptions.None) as byte[];
+            if (regValue == null || regValue.Length != sizeof(REG_TZI_FORMAT))
+            {
+                dtzi = default;
+                return false;
+            }
+            fixed (byte * pBytes = &regValue[0])
+                dtzi = *(REG_TZI_FORMAT *)pBytes;
+            return true;
+        }
+
+        /// <summary>
+        /// Helper function that compares the StandardBias and StandardDate portion a
+        /// TimeZoneInformation struct to a time zone registry entry.
+        /// </summary>
+        private static bool TryCompareStandardDate(in TIME_ZONE_INFORMATION timeZone, in REG_TZI_FORMAT registryTimeZoneInfo) =>
+            timeZone.Bias == registryTimeZoneInfo.Bias &&
+            timeZone.StandardBias == registryTimeZoneInfo.StandardBias &&
+            timeZone.StandardDate.Equals(registryTimeZoneInfo.StandardDate);
+
+        /// <summary>
+        /// Helper function that compares a TimeZoneInformation struct to a time zone registry entry.
+        /// </summary>
+        private static bool TryCompareTimeZoneInformationToRegistry(in TIME_ZONE_INFORMATION timeZone, string id, out bool dstDisabled)
+        {
+            dstDisabled = false;
+
+            using (RegistryKey key = Registry.LocalMachine.OpenSubKey(TimeZonesRegistryHive + "\\" + id, writable: false))
+            {
+                if (key == null)
+                {
+                    return false;
+                }
+
+                REG_TZI_FORMAT registryTimeZoneInfo;
+                if (!TryGetTimeZoneEntryFromRegistry(key, TimeZoneInfoValue, out registryTimeZoneInfo))
+                {
+                    return false;
+                }
+
+                //
+                // first compare the bias and standard date information between the data from the Win32 API
+                // and the data from the registry...
+                //
+                bool result = TryCompareStandardDate(timeZone, registryTimeZoneInfo);
+
+                if (!result)
+                {
+                    return false;
+                }
+
+                result = dstDisabled || CheckDaylightSavingTimeNotSupported(timeZone) ||
+                    //
+                    // since Daylight Saving Time is not "disabled", do a straight comparision between
+                    // the Win32 API data and the registry data ...
+                    //
+                    (timeZone.DaylightBias == registryTimeZoneInfo.DaylightBias &&
+                    timeZone.DaylightDate.Equals(registryTimeZoneInfo.DaylightDate));
+
+                // Finally compare the "StandardName" string value...
+                //
+                // we do not compare "DaylightName" as this TimeZoneInformation field may contain
+                // either "StandardName" or "DaylightName" depending on the time of year and current machine settings
+                //
+                if (result)
+                {
+                    string registryStandardName = key.GetValue(StandardValue, string.Empty, RegistryValueOptions.None) as string;
+                    result = string.Equals(registryStandardName, timeZone.GetStandardName(), StringComparison.Ordinal);
+                }
+                return result;
+            }
+        }
+
+        /// <summary>
+        /// Helper function for retrieving a localized string resource via MUI.
+        /// The function expects a string in the form: "@resource.dll, -123"
+        ///
+        /// "resource.dll" is a language-neutral portable executable (LNPE) file in
+        /// the %windir%\system32 directory.  The OS is queried to find the best-fit
+        /// localized resource file for this LNPE (ex: %windir%\system32\en-us\resource.dll.mui).
+        /// If a localized resource file exists, we LoadString resource ID "123" and
+        /// return it to our caller.
+        /// </summary>
+        private static string TryGetLocalizedNameByMuiNativeResource(string resource)
+        {
+            if (string.IsNullOrEmpty(resource))
+            {
+                return string.Empty;
+            }
+
+            // parse "@tzres.dll, -100"
+            //
+            // filePath   = "C:\Windows\System32\tzres.dll"
+            // resourceId = -100
+            //
+            string[] resources = resource.Split(',');
+            if (resources.Length != 2)
+            {
+                return string.Empty;
+            }
+
+            string filePath;
+            int resourceId;
+
+            // get the path to Windows\System32
+            string system32 = Environment.SystemDirectory;
+
+            // trim the string "@tzres.dll" => "tzres.dll"
+            string tzresDll = resources[0].TrimStart('@');
+
+            try
+            {
+                filePath = Path.Combine(system32, tzresDll);
+            }
+            catch (ArgumentException)
+            {
+                // there were probably illegal characters in the path
+                return string.Empty;
+            }
+
+            if (!int.TryParse(resources[1], NumberStyles.Integer, CultureInfo.InvariantCulture, out resourceId))
+            {
+                return string.Empty;
+            }
+            resourceId = -resourceId;
+
+            try
+            {
+                StringBuilder fileMuiPath = StringBuilderCache.Acquire(Interop.Kernel32.MAX_PATH);
+                fileMuiPath.Length = Interop.Kernel32.MAX_PATH;
+                int fileMuiPathLength = Interop.Kernel32.MAX_PATH;
+                int languageLength = 0;
+                long enumerator = 0;
+
+                bool succeeded = Interop.Kernel32.GetFileMUIPath(
+                                        Interop.Kernel32.MUI_PREFERRED_UI_LANGUAGES,
+                                        filePath, null /* language */, ref languageLength,
+                                        fileMuiPath, ref fileMuiPathLength, ref enumerator);
+                if (!succeeded)
+                {
+                    StringBuilderCache.Release(fileMuiPath);
+                    return string.Empty;
+                }
+                return TryGetLocalizedNameByNativeResource(StringBuilderCache.GetStringAndRelease(fileMuiPath), resourceId);
+            }
+            catch (EntryPointNotFoundException)
+            {
+                return string.Empty;
+            }
+        }
+
+        /// <summary>
+        /// Helper function for retrieving a localized string resource via a native resource DLL.
+        /// The function expects a string in the form: "C:\Windows\System32\en-us\resource.dll"
+        ///
+        /// "resource.dll" is a language-specific resource DLL.
+        /// If the localized resource DLL exists, LoadString(resource) is returned.
+        /// </summary>
+        private static string TryGetLocalizedNameByNativeResource(string filePath, int resource)
+        {
+            using (SafeLibraryHandle handle =
+                       Interop.Kernel32.LoadLibraryEx(filePath, IntPtr.Zero, Interop.Kernel32.LOAD_LIBRARY_AS_DATAFILE))
+            {
+                if (!handle.IsInvalid)
+                {
+                    const int LoadStringMaxLength = 500;
+
+                    StringBuilder localizedResource = StringBuilderCache.Acquire(LoadStringMaxLength);
+
+                    int result = Interop.User32.LoadString(handle, resource,
+                                     localizedResource, LoadStringMaxLength);
+
+                    if (result != 0)
+                    {
+                        return StringBuilderCache.GetStringAndRelease(localizedResource);
+                    }
+                }
+            }
+            return string.Empty;
+        }
+
+        /// <summary>
+        /// Helper function for retrieving the DisplayName, StandardName, and DaylightName from the registry
+        ///
+        /// The function first checks the MUI_ key-values, and if they exist, it loads the strings from the MUI
+        /// resource dll(s).  When the keys do not exist, the function falls back to reading from the standard
+        /// key-values
+        /// </summary>
+        private static void GetLocalizedNamesByRegistryKey(RegistryKey key, out string displayName, out string standardName, out string daylightName)
+        {
+            displayName = string.Empty;
+            standardName = string.Empty;
+            daylightName = string.Empty;
+
+            // read the MUI_ registry keys
+            string displayNameMuiResource = key.GetValue(MuiDisplayValue, string.Empty, RegistryValueOptions.None) as string;
+            string standardNameMuiResource = key.GetValue(MuiStandardValue, string.Empty, RegistryValueOptions.None) as string;
+            string daylightNameMuiResource = key.GetValue(MuiDaylightValue, string.Empty, RegistryValueOptions.None) as string;
+
+            // try to load the strings from the native resource DLL(s)
+            if (!string.IsNullOrEmpty(displayNameMuiResource))
+            {
+                displayName = TryGetLocalizedNameByMuiNativeResource(displayNameMuiResource);
+            }
+
+            if (!string.IsNullOrEmpty(standardNameMuiResource))
+            {
+                standardName = TryGetLocalizedNameByMuiNativeResource(standardNameMuiResource);
+            }
+
+            if (!string.IsNullOrEmpty(daylightNameMuiResource))
+            {
+                daylightName = TryGetLocalizedNameByMuiNativeResource(daylightNameMuiResource);
+            }
+
+            // fallback to using the standard registry keys
+            if (string.IsNullOrEmpty(displayName))
+            {
+                displayName = key.GetValue(DisplayValue, string.Empty, RegistryValueOptions.None) as string;
+            }
+            if (string.IsNullOrEmpty(standardName))
+            {
+                standardName = key.GetValue(StandardValue, string.Empty, RegistryValueOptions.None) as string;
+            }
+            if (string.IsNullOrEmpty(daylightName))
+            {
+                daylightName = key.GetValue(DaylightValue, string.Empty, RegistryValueOptions.None) as string;
+            }
+        }
+
+        /// <summary>
+        /// Helper function that takes a string representing a <time_zone_name> registry key name
+        /// and returns a TimeZoneInfo instance.
+        /// </summary>
+        private static TimeZoneInfoResult TryGetTimeZoneFromLocalMachine(string id, out TimeZoneInfo value, out Exception e)
+        {
+            e = null;
+
+            // Standard Time Zone Registry Data
+            // -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
+            // HKLM
+            //     Software
+            //         Microsoft
+            //             Windows NT
+            //                 CurrentVersion
+            //                     Time Zones
+            //                         <time_zone_name>
+            // * STD,         REG_SZ "Standard Time Name"
+            //                       (For OS installed zones, this will always be English)
+            // * MUI_STD,     REG_SZ "@tzres.dll,-1234"
+            //                       Indirect string to localized resource for Standard Time,
+            //                       add "%windir%\system32\" after "@"
+            // * DLT,         REG_SZ "Daylight Time Name"
+            //                       (For OS installed zones, this will always be English)
+            // * MUI_DLT,     REG_SZ "@tzres.dll,-1234"
+            //                       Indirect string to localized resource for Daylight Time,
+            //                       add "%windir%\system32\" after "@"
+            // * Display,     REG_SZ "Display Name like (GMT-8:00) Pacific Time..."
+            // * MUI_Display, REG_SZ "@tzres.dll,-1234"
+            //                       Indirect string to localized resource for the Display,
+            //                       add "%windir%\system32\" after "@"
+            // * TZI,         REG_BINARY REG_TZI_FORMAT
+            //
+            using (RegistryKey key = Registry.LocalMachine.OpenSubKey(TimeZonesRegistryHive + "\\" + id, writable: false))
+            {
+                if (key == null)
+                {
+                    value = null;
+                    return TimeZoneInfoResult.TimeZoneNotFoundException;
+                }
+
+                REG_TZI_FORMAT defaultTimeZoneInformation;
+                if (!TryGetTimeZoneEntryFromRegistry(key, TimeZoneInfoValue, out defaultTimeZoneInformation))
+                {
+                    // the registry value could not be cast to a byte array
+                    value = null;
+                    return TimeZoneInfoResult.InvalidTimeZoneException;
+                }
+
+                AdjustmentRule[] adjustmentRules;
+                if (!TryCreateAdjustmentRules(id, defaultTimeZoneInformation, out adjustmentRules, out e, defaultTimeZoneInformation.Bias))
+                {
+                    value = null;
+                    return TimeZoneInfoResult.InvalidTimeZoneException;
+                }
+
+                GetLocalizedNamesByRegistryKey(key, out string displayName, out string standardName, out string daylightName);
+
+                try
+                {
+                    value = new TimeZoneInfo(
+                        id,
+                        new TimeSpan(0, -(defaultTimeZoneInformation.Bias), 0),
+                        displayName,
+                        standardName,
+                        daylightName,
+                        adjustmentRules,
+                        disableDaylightSavingTime: false);
+
+                    return TimeZoneInfoResult.Success;
+                }
+                catch (ArgumentException ex)
+                {
+                    // TimeZoneInfo constructor can throw ArgumentException and InvalidTimeZoneException
+                    value = null;
+                    e = ex;
+                    return TimeZoneInfoResult.InvalidTimeZoneException;
+                }
+                catch (InvalidTimeZoneException ex)
+                {
+                    // TimeZoneInfo constructor can throw ArgumentException and InvalidTimeZoneException
+                    value = null;
+                    e = ex;
+                    return TimeZoneInfoResult.InvalidTimeZoneException;
+                }
+            }
+        }
+    }
+}