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| <!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN" |
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| <!-- 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.local_time.time_zone_base"> |
| <title>Time Zone (abstract)</title> |
| |
| <link linkend="time_zone_base_intro">Introduction</link> -- |
| <link linkend="time_zone_base_header">Header</link> -- |
| <link linkend="time_zone_base_constr">Construction</link> -- |
| <link linkend="time_zone_base_accessors">Accessors</link> |
| |
| <anchor id="time_zone_base_intro" /> |
| <bridgehead renderas="sect3">Introduction</bridgehead> |
| <para> |
| The time_zone_base class is an abstract base class template for representing time zones. Time zones are a set of data and rules that provide information about a time zone. The date_time library handles time_zones by means of a boost::shared_ptr<time_zone_base>. A user's custom time zone class will work in the date_time library by means of this shared_ptr. |
| </para> |
| <para> |
| For convienience, the time_zone_base class is typedef'd as time_zone. All references in the documentation to time_zone, are referring to this typedef. |
| </para> |
| |
| <anchor id="time_zone_base_header" /> |
| <bridgehead renderas="sect3">Header</bridgehead> |
| <para> |
| The time_zone_base class is defined in the header: |
| <programlisting>#include "boost/date_time/time_zone_base.hpp" |
| </programlisting> |
| </para> |
| |
| <anchor id="time_zone_base_constr" /> |
| <bridgehead renderas="sect3">Construction</bridgehead> |
| <para> |
| A default constructor is provided in the time_zone_base class. There are no private data members in this base class to initialize. |
| </para> |
| <para> |
| Template parameters are time_type (typically posix_time::ptime) and CharT (defaults to char). |
| </para> |
| |
| <anchor id="time_zone_base_accessors" /> |
| <bridgehead renderas="sect3">Accessors</bridgehead> |
| <para> |
| All of the accessors listed here are pure virtual functions. |
| </para> |
| <para> |
| <informaltable frame="all"> |
| <tgroup cols="2"> |
| <thead> |
| <row> |
| <entry>Syntax</entry> |
| <entry>Description</entry> |
| </row> |
| </thead> |
| <tbody> |
| <row> |
| <entry valign="top"><screen> |
| string_type dst_zone_abbrev();</screen></entry> |
| <entry>Returns the daylight savings abbreviation for the represented time zone.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| string_type std_zone_abbrev();</screen></entry> |
| <entry>Returns the standard abbreviation for the represented time zone.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| string_type dst_zone_name();</screen></entry> |
| <entry>Returns the daylight savings name for the represented time zone.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| string_type std_zone_name();</screen></entry> |
| <entry>Returns the standard name for the represented time zone.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen>bool has_dst();</screen></entry> |
| <entry>Returns true if this time zone does not make a daylight savings shift.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| time_type dst_local_start_time(year_type);</screen></entry> |
| <entry>The date and time daylight savings time begins in given year.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| time_type dst_local_end_time(year_type);</screen></entry> |
| <entry valign="top">The date and time daylight savings time ends in given year.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| time_duration_type base_utc_offset();</screen></entry> |
| <entry>The amount of time offset from UTC (typically in hours).</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| time_duration_type dst_offset();</screen></entry> |
| <entry>The amount of time shifted during daylight savings.</entry> |
| </row> |
| <row> |
| <entry valign="top"><screen> |
| std::string to_posix_string();</screen></entry> |
| <entry>Returns a posix time zone string representation of this time_zone_base object. For a detailed description of a posix time zone string see <link linkend="date_time.local_time.posix_time_zone">posix_time_zone</link>.</entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </informaltable> |
| </para> |
| |
| </section> |