boost_1_45_0/libs/date_time/xmldoc/ex_time_periods.xml

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<!DOCTYPE library PUBLIC "-//Boost//DTD BoostBook XML V1.0//EN" 
"../../../tools/boostbook/dtd/boostbook.dtd">

<!-- Copyright (c) 2001-2004 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.time_periods">
  <title>Time Periods</title>

  <para>
    Demonstrate some simple uses of time periods. 
  </para>
  <programlisting>
    <![CDATA[

  /* Some simple examples of constructing and calculating with times
   * Returns:
   * [2002-Feb-01 00:00:00/2002-Feb-01 23:59:59.999999999] 
   * contains 2002-Feb-01 03:00:05
   * [2002-Feb-01 00:00:00/2002-Feb-01 23:59:59.999999999] 
   * intersected with
   * [2002-Feb-01 00:00:00/2002-Feb-01 03:00:04.999999999] 
   * is 
   * [2002-Feb-01 00:00:00/2002-Feb-01 03:00:04.999999999]
   */

  #include "boost/date_time/posix_time/posix_time.hpp"
  #include <iostream>

  using namespace boost::posix_time;
  using namespace boost::gregorian;

  //Create a simple period class to contain all the times in a day
  class day_period : public time_period
  {
  public:
    day_period(date d) : time_period(ptime(d),//midnight
                                     ptime(d,hours(24)))
    {}

  };

  int
  main() 
  {

    date d(2002,Feb,1); //an arbitrary date
    //a period that represents a day  
    day_period dp(d);
    ptime t(d, hours(3)+seconds(5)); //an arbitray time on that day
    if (dp.contains(t)) {
      std::cout << to_simple_string(dp) << " contains "
                << to_simple_string(t)  << std::endl;
    }
    //a period that represents part of the day
    time_period part_of_day(ptime(d, hours(0)), t);
    //intersect the 2 periods and print the results
    if (part_of_day.intersects(dp)) {
      time_period result = part_of_day.intersection(dp);
      std::cout << to_simple_string(dp) << " intersected with\n"
                << to_simple_string(part_of_day) << " is \n"
                << to_simple_string(result) << std::endl;
    }
      
    
    return 0;
  }

    ]]>
  </programlisting>
</section>