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Porting date and time topics from MSDN (dotnet#992)
* Porting date and time topics from MSDN Previously reviewed - closes dotnet#224 * Fixed broken links and TOC title * Fixed lowercase API names * Still trying to fix build warnings * Fixed reference links * Fixed more reference links * Remove colon from how to metadata * Adressed feedback * Fixed title metadata
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‎docs/standard/datetime/access-utc-and-local.md

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---
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title: "How to: access the predefined UTC and local time zone objects"
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description: How to access the predefined UTC and local time zone objects
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keywords: .NET, .NET Core
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author: stevehoag
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manager: wpickett
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ms.date: 08/11/2016
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ms.topic: article
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ms.prod: .net-core
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ms.technology: .net-core-technologies
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ms.devlang: dotnet
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ms.assetid: 13454d47-d957-421b-9ecd-940058b8835e
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---
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# How to: access the predefined UTC and local time zone objects
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The [System.TimeZoneInfo](xref:System.TimeZoneInfo) class provides two properties, `Utc` and `Local`, that give your code access to predefined time zone objects. This topic discusses how to access the `TimeZoneInfo` objects returned by those properties.
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## To access the Coordinated Universal Time (UTC) TimeZoneInfo object
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1. Use the **static** (**Shared** in Visual Basic) [TimeZoneInfo.Utc](xref:System.TimeZoneInfo.Utc) property to access Coordinated Universal Time.
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2. Rather than assigning the [TimeZoneInfo](xref:System.TimeZoneInfo) object returned by the property to an object variable, continue to access Coordinated Universal Time through the [TimeZoneInfo.Utc](xref:System.TimeZoneInfo.Utc) property.
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## To access the local time zone
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1. Use the **static** (**Shared** in Visual Basic) [TimeZoneInfo.Local](xref:System.TimeZoneInfo.Local) property to access the local system time zone.
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2. Rather than assigning the [TimeZoneInfo](xref:System.TimeZoneInfo) object returned by the property to an object variable, continue to access the local time zone through the [TimeZoneInfo.Local](xref:System.TimeZoneInfo.Local) property.
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## Example
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The following code uses the [TimeZoneInfo.Local](xref:System.TimeZoneInfo.Local) and [TimeZoneInfo.Utc](xref:System.TimeZoneInfo.Utc) properties to convert a time from the U.S. and Canadian Eastern Standard time zone, as well as to display the time zone name to the console.
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```csharp
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// Create Eastern Standard Time value and TimeZoneInfo object
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DateTime estTime = new DateTime(2007, 1, 1, 00, 00, 00);
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string timeZoneName = "Eastern Standard Time";
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try
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{
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TimeZoneInfo est = TimeZoneInfo.FindSystemTimeZoneById(timeZoneName);
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// Convert EST to local time
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DateTime localTime = TimeZoneInfo.ConvertTime(estTime, est, TimeZoneInfo.Local);
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Console.WriteLine("At {0} {1}, the local time is {2} {3}.",
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estTime,
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est,
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localTime,
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TimeZoneInfo.Local.IsDaylightSavingTime(localTime) ?
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TimeZoneInfo.Local.DaylightName :
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TimeZoneInfo.Local.StandardName);
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// Convert EST to UTC
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DateTime utcTime = TimeZoneInfo.ConvertTime(estTime, est, TimeZoneInfo.Utc);
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Console.WriteLine("At {0} {1}, the time is {2} {3}.",
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estTime,
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est,
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utcTime,
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TimeZoneInfo.Utc.StandardName);
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}
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catch (TimeZoneNotFoundException)
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{
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Console.WriteLine("The {0} zone cannot be found in the registry.",
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timeZoneName);
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}
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catch (InvalidTimeZoneException)
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{
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Console.WriteLine("The registry contains invalid data for the {0} zone.",
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timeZoneName);
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}
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```
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```vb
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' Create Eastern Standard Time value and TimeZoneInfo object
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Dim estTime As Date = #01/01/2007 00:00:00#
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Dim timeZoneName As String = "Eastern Standard Time"
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Try
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Dim est As TimeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById(timeZoneName)
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' Convert EST to local time
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Dim localTime As Date = TimeZoneInfo.ConvertTime(estTime, est, TimeZoneInfo.Local)
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Console.WriteLine("At {0} {1}, the local time is {2} {3}.", _
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estTime, _
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est, _
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localTime, _
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IIf(TimeZoneInfo.Local.IsDaylightSavingTime(localTime), _
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TimeZoneInfo.Local.DaylightName, _
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TimeZoneInfo.Local.StandardName))
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' Convert EST to UTC
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Dim utcTime As Date = TimeZoneInfo.ConvertTime(estTime, est, TimeZoneInfo.Utc)
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Console.WriteLine("At {0} {1}, the time is {2} {3}.", _
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estTime, _
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est, _
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utcTime, _
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TimeZoneInfo.Utc.StandardName)
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Catch e As TimeZoneNotFoundException
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Console.WriteLine("The {0} zone cannot be found in the registry.", _
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timeZoneName)
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Catch e As InvalidTimeZoneException
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Console.WriteLine("The registry contains invalid data for the {0} zone.", _
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timeZoneName)
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End Try
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```
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You should always access the local time zone through the [TimeZoneInfo.Local](xref:System.TimeZoneInfo.Local) property rather than assigning the local time zone to a [TimeZoneInfo](xref:System.TimeZoneInfo) object variable. Similarly, you should always access Coordinated Universal Time through the [TimeZoneInfo.Utc](xref:System.TimeZoneInfo.Utc) property rather than assigning the UTC zone to a [TimeZoneInfo](xref:System.TimeZoneInfo) object variable. This prevents the [TimeZoneInfo](xref:System.TimeZoneInfo) object variable from being invalidated by an external method.
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## See Also
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[Dates, times, and time zones](index.md)
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[Finding the time zones defined on a local system](finding-the-time-zones-on-local-system.md)

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