ceph/src/boost/libs/date_time/xmldoc/ex_dates_as_strings.xml

   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) 2001-2004 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.examples.dates_as_strings">
  11   <title>Dates as Strings</title>
  12
  13   <para>
  14     Various parsing and output of strings.
  15   </para>
  16   <programlisting>
  17     <![CDATA[
  18
  19   /* The following is a simple example that shows conversion of dates
  20    * to and from a std::string.
  21    *
  22    * Expected output:
  23    * 2001-Oct-09
  24    * 2001-10-09
  25    * Tuesday October 9, 2001
  26    * An expected exception is next:
  27    * Exception: Month number is out of range 1..12
  28    */
  29
  30   #include "boost/date_time/gregorian/gregorian.hpp"
  31   #include <iostream>
  32   #include <string>
  33
  34   int
  35   main()
  36   {
  37
  38     using namespace boost::gregorian;
  39
  40     try {
  41       // The following date is in ISO 8601 extended format (CCYY-MM-DD)
  42       std::string s("2001-10-9"); //2001-October-09
  43       date d(from_simple_string(s));
  44       std::cout << to_simple_string(d) << std::endl;
  45
  46       //Read ISO Standard(CCYYMMDD) and output ISO Extended
  47       std::string ud("20011009"); //2001-Oct-09
  48       date d1(from_undelimited_string(ud));
  49       std::cout << to_iso_extended_string(d1) << std::endl;
  50
  51       //Output the parts of the date - Tuesday October 9, 2001
  52       date::ymd_type ymd = d1.year_month_day();
  53       greg_weekday wd = d1.day_of_week();
  54       std::cout << wd.as_long_string() << " "
  55                 << ymd.month.as_long_string() << " "
  56                 << ymd.day << ", " << ymd.year
  57                 << std::endl;
  58
  59       //Let's send in month 25 by accident and create an exception
  60       std::string bad_date("20012509"); //2001-??-09
  61       std::cout << "An expected exception is next: " << std::endl;
  62       date wont_construct(from_undelimited_string(bad_date));
  63       //use wont_construct so compiler doesn't complain, but you wont get here!
  64       std::cout << "oh oh, you shouldn't reach this line: "
  65                 << to_iso_string(wont_construct) << std::endl;
  66     }
  67     catch(std::exception& e) {
  68       std::cout << "  Exception: " <<  e.what() << std::endl;
  69     }
  70
  71
  72     return 0;
  73   }
  74
  75     ]]>
  76   </programlisting>
  77 </section>