1<?xml version="1.0" encoding="utf-8"?> 2<!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN" 3"../../../tools/boostbook/dtd/boostbook.dtd"> 4 5<!-- Copyright (c) 2001-2005 CrystalClear Software, Inc. 6 Subject to the Boost Software License, Version 1.0. 7 (See accompanying file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt) 8--> 9 10<section id="date_time.local_time.time_zone_base"> 11 <title>Time Zone (abstract)</title> 12 13 <link linkend="time_zone_base_intro">Introduction</link> -- 14 <link linkend="time_zone_base_header">Header</link> -- 15 <link linkend="time_zone_base_constr">Construction</link> -- 16 <link linkend="time_zone_base_accessors">Accessors</link> 17 18 <anchor id="time_zone_base_intro" /> 19 <bridgehead renderas="sect3">Introduction</bridgehead> 20 <para> 21 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. 22 </para> 23 <para> 24 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. 25 </para> 26 27 <anchor id="time_zone_base_header" /> 28 <bridgehead renderas="sect3">Header</bridgehead> 29 <para> 30 The time_zone_base class is defined in the header: 31 <programlisting>#include "boost/date_time/time_zone_base.hpp" 32 </programlisting> 33 </para> 34 35 <anchor id="time_zone_base_constr" /> 36 <bridgehead renderas="sect3">Construction</bridgehead> 37 <para> 38 A default constructor is provided in the time_zone_base class. There are no private data members in this base class to initialize. 39 </para> 40 <para> 41 Template parameters are time_type (typically posix_time::ptime) and CharT (defaults to char). 42 </para> 43 44 <anchor id="time_zone_base_accessors" /> 45 <bridgehead renderas="sect3">Accessors</bridgehead> 46 <para> 47 All of the accessors listed here are pure virtual functions. 48 </para> 49 <para> 50 <informaltable frame="all"> 51 <tgroup cols="2"> 52 <thead> 53 <row> 54 <entry>Syntax</entry> 55 <entry>Description</entry> 56 </row> 57 </thead> 58 <tbody> 59 <row> 60 <entry valign="top"><screen> 61string_type dst_zone_abbrev();</screen></entry> 62 <entry>Returns the daylight savings abbreviation for the represented time zone.</entry> 63 </row> 64 <row> 65 <entry valign="top"><screen> 66string_type std_zone_abbrev();</screen></entry> 67 <entry>Returns the standard abbreviation for the represented time zone.</entry> 68 </row> 69 <row> 70 <entry valign="top"><screen> 71string_type dst_zone_name();</screen></entry> 72 <entry>Returns the daylight savings name for the represented time zone.</entry> 73 </row> 74 <row> 75 <entry valign="top"><screen> 76string_type std_zone_name();</screen></entry> 77 <entry>Returns the standard name for the represented time zone.</entry> 78 </row> 79 <row> 80 <entry valign="top"><screen>bool has_dst();</screen></entry> 81 <entry>Returns true if this time zone does not make a daylight savings shift.</entry> 82 </row> 83 <row> 84 <entry valign="top"><screen> 85time_type dst_local_start_time(year_type);</screen></entry> 86 <entry>The date and time daylight savings time begins in given year.</entry> 87 </row> 88 <row> 89 <entry valign="top"><screen> 90time_type dst_local_end_time(year_type);</screen></entry> 91 <entry valign="top">The date and time daylight savings time ends in given year.</entry> 92 </row> 93 <row> 94 <entry valign="top"><screen> 95time_duration_type base_utc_offset();</screen></entry> 96 <entry>The amount of time offset from UTC (typically in hours).</entry> 97 </row> 98 <row> 99 <entry valign="top"><screen> 100time_duration_type dst_offset();</screen></entry> 101 <entry>The amount of time shifted during daylight savings.</entry> 102 </row> 103 <row> 104 <entry valign="top"><screen> 105std::string to_posix_string();</screen></entry> 106 <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> 107 </row> 108 </tbody> 109 </tgroup> 110 </informaltable> 111 </para> 112 113</section> 114