date_time/xmldoc/usage_examples.xml

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     Subject to the Boost Software License, Version 1.0. 
     (See accompanying file LICENSE-1.0 or  http://www.boost.org/LICENSE-1.0)
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<section id="date_time.examples.general_usage_examples">
  <title>General Usage Examples</title>

  <para>
    The following provides some sample usage of dates.
    See <link linkend="date_time.gregorian">Date Programming</link> 
    for more details.

    <programlisting>    
	 using namespace boost::gregorian; 
	 date weekstart(2002,Feb,1);
	 date weekend  = weekstart + week(1);
	 date d2 = d1 + days(5);
	 date today = day_clock::local_day();
	 if (d2 &gt;= today) {} //date comparison operators
	 
	 date_period thisWeek(d1,d2);
	 if (thisWeek.contains(today)) {}//do something
	
	 //iterate and print the week
	 day_iterator itr(weekstart);
	 while (itr &lt;= weekend) {
	   std::cout &lt;&lt; (*itr) &lt;&lt; std::endl;
           ++itr;
	 }  
         //input streaming
         std::stringstream ss("2004-Jan-1");
         ss &gt;&gt; d3;
        
         //localized i/o using facets
         std::locale global;
         std::locale german(global, 
                            new date_facet(de_short_month_names, 
                                           de_long_month_names,
                                           de_special_value_names,
                                           de_long_weekday_names,
                                           de_long_weekday_names,
                                           '.', 
                                           boost::date_time::ymd_order_dmy));
         std::cout.imbue(global2); 
         date d4(2002, Oct, 1);
         std::cout &lt;&lt; d4; //01.Okt.2002

         //date generator functions
         date d5 = next_weekday(d4, Sunday); //calculate sunday following d4

         //define a shorthand for the nth_day_of_the_week_in_month function object
	 typedef nth_day_of_the_week_in_month nth_dow;
         //US labor day is first Monday in Sept
	 nth_dow labor_day(nth_dow::first,Monday, Sep); 
	 date d6 = labor_day.get_date(2004); //calculate a specific date from functor
    </programlisting>    

      The following provides some example code using times.
      See <link linkend="date_time.posix_time">Time Programming</link> 
      for more details.

    <programlisting>    
	 use namespace boost::posix_time; 
	 date d(2002,Feb,1); //an arbitrary date
	 ptime t1(d, hours(5)+nanosec(100)); //date + time of day offset
	 ptime t2 = t1 - minutes(4)+seconds(2);
	 ptime now = second_clock::local_time(); //use the clock
	 date today = now.date(); //Get the date part out of the time
	 date tommorrow = today + date_duration(1);
	 ptime tommorrow_start(tommorrow); //midnight 

         //input streaming
         std::stringstream ss("2004-Jan-1 05:21:33.20");
         ss &gt;&gt; t2;

	 //starting at current time iterator adds by one hour
	 time_iterator titr(now,hours(1)); 
	 for (; titr &lt; tommorrow_start; ++titr) {
	   std::cout &lt;&lt; (*titr) &lt;&lt; std::endl;
	 }

    </programlisting>    
  </para>
  
  <link linkend="top">top</link>
</section>