| <?xml version="1.0" encoding="utf-8"?> |
| <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN" |
| "../../../tools/boostbook/dtd/boostbook.dtd"> |
| |
| <!-- Copyright (c) 2001-2005 CrystalClear Software, Inc. |
| Subject to the Boost Software License, Version 1.0. |
| (See accompanying file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt) |
| --> |
| |
| <section id="date_time.examples.flight"> |
| <title>Flight Time Example</title> |
| |
| <para>This example shows a program that calculates the arrival time of a plane that flys from Phoenix to New York. During the flight New York shifts into daylight savings time (Phoenix doesn't because Arizona doesn't use dst).</para> |
| |
| <programlisting> |
| <literal> |
| <phrase role="preprocessor">#include</phrase><phrase role="string"> "boost/date_time/local_time/local_time.hpp"</phrase><phrase role="preprocessor"> |
| #include</phrase><phrase role="special"> <</phrase><phrase role="identifier">iostream</phrase><phrase role="special">></phrase><phrase role="comment"> |
| |
| /* This example shows a program that calculates the arrival time of a plane |
| * that flys from Phoenix to New York. During the flight New York shifts |
| * into daylight savings time (Phoenix doesn't because Arizona doesn't use |
| * dst). |
| * |
| * |
| */</phrase><phrase role="keyword"> |
| |
| int</phrase><phrase role="identifier"> main</phrase><phrase role="special">()</phrase><phrase role="special"> |
| {</phrase><phrase role="keyword"> |
| using</phrase><phrase role="keyword"> namespace</phrase><phrase role="identifier"> boost</phrase><phrase role="special">::</phrase><phrase role="identifier">gregorian</phrase><phrase role="special">;</phrase><phrase role="keyword"> |
| using</phrase><phrase role="keyword"> namespace</phrase><phrase role="identifier"> boost</phrase><phrase role="special">::</phrase><phrase role="identifier">local_time</phrase><phrase role="special">;</phrase><phrase role="keyword"> |
| using</phrase><phrase role="keyword"> namespace</phrase><phrase role="identifier"> boost</phrase><phrase role="special">::</phrase><phrase role="identifier">posix_time</phrase><phrase role="special">;</phrase><phrase role="comment"> |
| |
| |
| //setup some timezones for creating and adjusting local times |
| //This user editable file can be found in libs/date_time/data. |
| </phrase><phrase role="identifier"> tz_database</phrase><phrase role="identifier"> tz_db</phrase><phrase role="special">;</phrase><phrase role="identifier"> |
| tz_db</phrase><phrase role="special">.</phrase><phrase role="identifier">load_from_file</phrase><phrase role="special">(</phrase><phrase role="string">"date_time_zonespec.csv"</phrase><phrase role="special">);</phrase><phrase role="identifier"> |
| time_zone_ptr</phrase><phrase role="identifier"> nyc_tz</phrase><phrase role="special"> =</phrase><phrase role="identifier"> tz_db</phrase><phrase role="special">.</phrase><phrase role="identifier">time_zone_from_region</phrase><phrase role="special">(</phrase><phrase role="string">"America/New_York"</phrase><phrase role="special">);</phrase><phrase role="comment"> |
| //Use a |
| </phrase><phrase role="identifier"> time_zone_ptr</phrase><phrase role="identifier"> phx_tz</phrase><phrase role="special">(</phrase><phrase role="keyword">new</phrase><phrase role="identifier"> posix_time_zone</phrase><phrase role="special">(</phrase><phrase role="string">"MST-07:00:00"</phrase><phrase role="special">));</phrase><phrase role="comment"> |
| |
| //local departure time in phoenix is 11 pm on april 2 2005 |
| // (ny changes to dst on apr 3 at 2 am) |
| </phrase><phrase role="identifier"> local_date_time</phrase><phrase role="identifier"> phx_departure</phrase><phrase role="special">(</phrase><phrase role="identifier">date</phrase><phrase role="special">(</phrase><phrase role="number">2005</phrase><phrase role="special">,</phrase><phrase role="identifier"> Apr</phrase><phrase role="special">,</phrase><phrase role="number"> 2</phrase><phrase role="special">),</phrase><phrase role="identifier"> hours</phrase><phrase role="special">(</phrase><phrase role="number">23</phrase><phrase role="special">),</phrase><phrase role="identifier"> |
| phx_tz</phrase><phrase role="special">,</phrase><phrase role="identifier"> |
| local_date_time</phrase><phrase role="special">::</phrase><phrase role="identifier">NOT_DATE_TIME_ON_ERROR</phrase><phrase role="special">);</phrase><phrase role="identifier"> |
| |
| time_duration</phrase><phrase role="identifier"> flight_length</phrase><phrase role="special"> =</phrase><phrase role="identifier"> hours</phrase><phrase role="special">(</phrase><phrase role="number">4</phrase><phrase role="special">)</phrase><phrase role="special"> +</phrase><phrase role="identifier"> minutes</phrase><phrase role="special">(</phrase><phrase role="number">30</phrase><phrase role="special">);</phrase><phrase role="identifier"> |
| local_date_time</phrase><phrase role="identifier"> phx_arrival</phrase><phrase role="special"> =</phrase><phrase role="identifier"> phx_departure</phrase><phrase role="special"> +</phrase><phrase role="identifier"> flight_length</phrase><phrase role="special">;</phrase><phrase role="identifier"> |
| local_date_time</phrase><phrase role="identifier"> nyc_arrival</phrase><phrase role="special"> =</phrase><phrase role="identifier"> phx_arrival</phrase><phrase role="special">.</phrase><phrase role="identifier">local_time_in</phrase><phrase role="special">(</phrase><phrase role="identifier">nyc_tz</phrase><phrase role="special">);</phrase><phrase role="identifier"> |
| |
| std</phrase><phrase role="special">::</phrase><phrase role="identifier">cout</phrase><phrase role="special"> <<</phrase><phrase role="string"> "departure phx time: "</phrase><phrase role="special"> <<</phrase><phrase role="identifier"> phx_departure</phrase><phrase role="special"> <<</phrase><phrase role="identifier"> std</phrase><phrase role="special">::</phrase><phrase role="identifier">endl</phrase><phrase role="special">;</phrase><phrase role="identifier"> |
| std</phrase><phrase role="special">::</phrase><phrase role="identifier">cout</phrase><phrase role="special"> <<</phrase><phrase role="string"> "arrival phx time: "</phrase><phrase role="special"> <<</phrase><phrase role="identifier"> phx_arrival</phrase><phrase role="special"> <<</phrase><phrase role="identifier"> std</phrase><phrase role="special">::</phrase><phrase role="identifier">endl</phrase><phrase role="special">;</phrase><phrase role="identifier"> |
| std</phrase><phrase role="special">::</phrase><phrase role="identifier">cout</phrase><phrase role="special"> <<</phrase><phrase role="string"> "arrival nyc time: "</phrase><phrase role="special"> <<</phrase><phrase role="identifier"> nyc_arrival</phrase><phrase role="special"> <<</phrase><phrase role="identifier"> std</phrase><phrase role="special">::</phrase><phrase role="identifier">endl</phrase><phrase role="special">;</phrase><phrase role="special"> |
| |
| }</phrase> |
| </literal> |
| </programlisting> |
| </section> |