<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <title>General Usage Examples</title> <link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> <meta name="generator" content="DocBook XSL Stylesheets V1.75.2"> <link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> <link rel="up" href="../../date_time.html" title="Chapter 5. Boost.Date_Time"> <link rel="prev" href="../../date_time.html" title="Chapter 5. Boost.Date_Time"> <link rel="next" href="../gregorian.html" title="Gregorian"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <table cellpadding="2" width="100%"><tr> <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td> <td align="center"><a href="../../../../index.html">Home</a></td> <td align="center"><a href="../../../../libs/libraries.htm">Libraries</a></td> <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> <td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> <td align="center"><a href="../../../../more/index.htm">More</a></td> </tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="../../date_time.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../date_time.html"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="../gregorian.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> </div> <div class="section"> <div class="titlepage"><div><div><h2 class="title" style="clear: both"> <a name="date_time.examples.general_usage_examples"></a>General Usage Examples</h2></div></div></div> <p> The following provides some sample usage of dates. See <a class="link" href="../gregorian.html" title="Gregorian">Date Programming</a> for more details. </p> <pre class="programlisting"><span class="keyword">using namespace</span> boost::gregorian; date weekstart(<span class="number">2002</span>,Feb,<span class="number">1</span>); date weekend = weekstart + week(<span class="number">1</span>); date d2 = d1 + days(<span class="number">5</span>); date today = day_clock::local_day(); if (d2 >= today) {} <span class="comment">//date comparison operators</span> date_period thisWeek(d1,d2); <span class="keyword">if</span> (thisWeek.contains(today)) {}<span class="comment">//do something //iterate and print the week</span> day_iterator itr(weekstart); <span class="keyword">while</span> (itr <= weekend) { std::cout << (*itr) << std::endl; ++itr; } <span class="comment">//input streaming</span> std::stringstream ss(<span class="string">"2004-Jan-1"</span>); ss >> d3; <span class="comment">//date generator functions</span> date d5 = next_weekday(d4, Sunday); <span class="comment">//calculate Sunday following d4 //US labor day is first Monday in Sept</span> nth_day_of_the_week_in_month labor_day(nth_dow::first,Monday, Sep); <span class="comment">//calculate a specific date for 2004 from functor</span> date d6 = labor_day.get_date(<span class="number">2004</span>); </pre> <p> The following provides some example code using times. See <a class="link" href="../posix_time.html" title="Posix Time">Time Programming</a> for more details. </p> <pre class="programlisting"><span class="keyword">using namespace</span> boost::posix_time; date d(<span class="number">2002</span>,Feb,<span class="number">1</span>); <span class="comment">//an arbitrary date</span> ptime t1(d, hours(<span class="number">5</span>)+nanosec(<span class="number">100</span>)); <span class="comment">//date + time of day offset</span> ptime t2 = t1 - minutes(<span class="number">4</span>)+seconds(<span class="number">2</span>); ptime now = second_clock::local_time(); <span class="comment">//use the clock</span> date today = now.date(); <span class="comment">//Get the date part out of the time</span> date tomorrow = today + date_duration(<span class="number">1</span>); ptime tomorrow_start(tomorrow); <span class="comment">//midnight //input streaming</span> std::stringstream ss(<span class="string">"2004-Jan-1 05:21:33.20"</span>); ss >> t2; <span class="comment">//starting at current time iterator adds by one hour</span> time_iterator titr(now,hours(<span class="number">1</span>)); <span class="keyword">for</span> (; titr < tomorrow_start; ++titr) { std::cout << (*titr) << std::endl; } </pre> <p> </p> <p> The following provides some example code using times. See <a class="link" href="../local_time.html" title="Local Time">Local Time Programming</a> for more details. </p> <pre class="programlisting"> <span class="keyword">using namespace</span> boost::local_time; <span class="comment">//setup some timezones for creating and adjusting times //first time zone uses the time zone file for regional timezone definitions</span> tz_database tz_db; tz_db.load_from_file(<span class="string">"date_time_zonespec.csv"</span>); time_zone_ptr nyc_tz = tz_db.time_zone_from_region(<span class="string">"America/New_York"</span>); <span class="comment">//This timezone uses a posix time zone string definition to create a time zone</span> time_zone_ptr phx_tz(new posix_time_zone(<span class="string">"MST-07:00:00"</span>)); <span class="comment">//local departure time in phoenix is 11 pm on April 2 2005 // Note that New York changes to daylight savings on Apr 3 at 2 am)</span> local_date_time phx_departure(date(<span class="number">2005</span>, Apr, <span class="number">2</span>), hours(<span class="number">23</span>), phx_tz, local_date_time::NOT_DATE_TIME_ON_ERROR); time_duration flight_length = hours(<span class="number">4</span>) + minutes(<span class="number">30</span>); local_date_time phx_arrival = phx_departure + flight_length; <span class="comment">//convert the phx time to a nyz time</span> local_date_time nyc_arrival = phx_arrival.local_time_in(nyc_tz); <span class="comment">//2005-Apr-03 06:30:00 EDT</span> std::cout << nyc_arrival << std::endl; </pre> <p> </p> </div> <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> <td align="left"></td> <td align="right"><div class="copyright-footer">Copyright © 2001-2005 CrystalClear Software, Inc<p>Subject to the Boost Software License, Version 1.0. (See accompanying file <code class="filename">LICENSE_1_0.txt</code> or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)</p> </div></td> </tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="../../date_time.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../date_time.html"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="../gregorian.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> </div> </body> </html>