timezoneconversion: -Time Zone Conversion Example

Download

Click on the following link to download -the example: TZExample.zip

Click: browse to view the example code.

Description

This example code first connects to -the time zone server (class RTz). Then it uses RTz::ConvertToLocalTime() to -convert a UTC time to local time. The time to convert and the time zone to -convert it to are randomly chosen. This demonstrates that the time zone server -can convert any time, past, present or future, for any time zone, as long -as a rule exists for the conversion. Conversion rules are stored in a native -Symbian OS database that is a compressed form of the Olson time zone database -(http://www.twinsun.com/tz/tz-link.htm). -The database can be configured by phone manufacturers to save space.

The -example then converts the current local time for the system time zone to the -current local time for a different time zone. This is a two stage process. -First, the local time is converted to UTC using RTz::ConvertToUniversalTime(). -When converting between local and UTC times for the current system time zone, -there is no need to specify the time zone ID. Then UTC is converted to local -time for the other time zone. Before the example terminates, the connection -to the server is closed.

No special capabilities are needed to do -time zone conversion.

Class CTzId identifies a -time zone. It stores the identifier either as text, (for instance Australia/Sydney), -or as a number. Numeric time zone IDs are assigned by the phone manufacturer, -so can vary from phone to phone.

For efficiency, the time zone server -caches a copy of a range of conversion rules for the current time zone. These -cached rules are actualised, meaning they have been expanded from the -encoded compact format as stored in the database, so are quicker to access.

Class CTzConverter, -which is not used in this example, provides an alternative conversion API -to RTz. It caches 5 years' worth of conversion rules for -a specific time zone (either the time zone specified in the conversion function, -or the system time zone), on the client side, so avoiding the need for an -an IPC call for each conversion. CTzConverter is more efficient -than RTz when doing multiple conversions for a single time -zone.

Usage

This is a console application, so does not -have a GUI. It builds an executable called TZExample.exe in -the standard location (\epoc32\release\winscw\<build_variant> for -CodeWarrior). After launching the executable, depending on the emulator you -are using, you may need to task away from the app launcher/shell screen to -view the console.

Class Summary

RTz

CTzId

TTime

+ + + + + +timezoneconversion: +Time Zone Conversion Example +

Download

Click on the following link to download +the example: TZExample.zip

Click: browse to view the example code.

Description

This example code first connects to +the time zone server (class RTz). Then it uses RTz::ConvertToLocalTime() to +convert a UTC time to local time. The time to convert and the time zone to +convert it to are randomly chosen. This demonstrates that the time zone server +can convert any time, past, present or future, for any time zone, as long +as a rule exists for the conversion. Conversion rules are stored in a native +Symbian database that is a compressed form of the Olson time +zone database (http://www.twinsun.com/tz/tz-link.htm). +The database can be configured by phone manufacturers to save space.

The +example then converts the current local time for the system time zone to the +current local time for a different time zone. This is a two stage process. +First, the local time is converted to UTC using RTz::ConvertToUniversalTime(). +When converting between local and UTC times for the current system time zone, +there is no need to specify the time zone ID. Then UTC is converted to local +time for the other time zone. Before the example terminates, the connection +to the server is closed.

No special capabilities are needed to do +time zone conversion.

Class CTzId identifies a +time zone. It stores the identifier either as text, (for instance Australia/Sydney), +or as a number. Numeric time zone IDs are assigned by the phone manufacturer, +so can vary from phone to phone.

For efficiency, the time zone server +caches a copy of a range of conversion rules for the current time zone. These +cached rules are actualised, meaning they have been expanded from the +encoded compact format as stored in the database, so are quicker to access.

Class CTzConverter, +which is not used in this example, provides an alternative conversion API +to RTz. It caches 5 years' worth of conversion rules for +a specific time zone (either the time zone specified in the conversion function, +or the system time zone), on the client side, so avoiding the need for an +an IPC call for each conversion. CTzConverter is more efficient +than RTz when doing multiple conversions for a single time +zone.

Usage

This is a console application, so does not +have a GUI. It builds an executable called TZExample.exe in +the standard location (\epoc32\release\winscw\<build_variant> for +CodeWarrior). After launching the executable, depending on the emulator you +are using, you may need to task away from the app launcher/shell screen to +view the console.

Class Summary

RTz

CTzId

TTime

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