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Class template local_adjustor

boost::date_time::local_adjustor — Template that simplifies the creation of local time calculator.


// In header: <boost/date_time/local_time_adjustor.hpp>

template<typename time_type, short utc_offset, typename dst_rule> 
class local_adjustor {
  // types
  typedef time_type::time_duration_type                                                                       time_duration_type;
  typedef time_type::date_type                                                                                date_type;         
  typedef static_local_time_adjustor< time_type, dst_rule, utc_adjustment< time_duration_type, utc_offset > > dst_adjustor;      

  // public static functions
  static time_type utc_to_local(const time_type &);
  static time_type 
  local_to_utc(const time_type &, date_time::dst_flags = date_time::calculate);


Use this template to create the timezone to utc convertors as required.

This class will also work for other regions that don't use dst and have a utc offset which is an integral number of hours.

Template Parameters -time_type – Time class to use -utc_offset – Number hours local time is adjust from utc -use_dst – true (default) if region uses dst, false otherwise For example:

   //eastern timezone is utc-5
typedef date_time::local_adjustor<ptime, -5, us_dst> us_eastern;
typedef date_time::local_adjustor<ptime, -6, us_dst> us_central;
typedef date_time::local_adjustor<ptime, -7, us_dst> us_mountain;
typedef date_time::local_adjustor<ptime, -8, us_dst> us_pacific;
typedef date_time::local_adjustor<ptime, -7, no_dst> us_arizona;

local_adjustor public static functions

  1. static time_type utc_to_local(const time_type & t);
    Convert a utc time to local time.
  2. static time_type 
    local_to_utc(const time_type & t, 
                 date_time::dst_flags dst = date_time::calculate);
    Convert a local time to utc.