from_days() [1/2]

static time_span xtd::time_span::from_days ( double  value )

static

Returns a xtd::time_span that represents a specified number of days, where the specification is accurate to the nearest millisecond.

Parameters

value

A number of days, accurate to the nearest millisecond.

Returns

An object that represents value.

Exceptions

xtd::overflow_exception	value is less than xtd::time_span::min_value or greater than xtd::time_span::max_value. -or- value is xtd::double_object::positive_infinity. -or- value is xtd::double_object::negative_infinity.
xtd::argument_exception	value is equal to xtd::double_object::NaN.

Examples

The following example creates several xtd::time_span objects using the xtd::time_span::from_days method.

#include <xtd/console>
#include <xtd/time_span>
#include <xtd/int64_object>
#include <xtd/string>
 
using namespace xtd;
 
void gen_time_span_from_days (double days) {
  // Crée un objet TimeSpan et une chaîne TimeSpan à partir
  // d'un nombre de jours.
  auto interval = time_span::from_days(days);
  auto time_interval = interval.to_string();
  
  // Remplit la fin de la chaîne TimeSpan avec des espaces si elle
  // ne contient pas de millisecondes.
  size_t index = time_interval.index_of( ':' );
  index = time_interval.index_of( '.', index );
  if (index == string::npos) time_interval += "        ";
  
  console::write_line("{0,21}{1,26}", days, time_interval);
}
 
int main() {
  console::write_line("This example of time_span::from_days(double)\n"
                      "generates the following output.\n" );
  console::write_line("{0,21}{1,19}",
                      "from_days", "time_span" );
  console::write_line("{0,21}{1,19}",
                      "---------", "---------" );
  
  gen_time_span_from_days(0.000000006);
  gen_time_span_from_days(0.000000017);
  gen_time_span_from_days(0.000123456);
  gen_time_span_from_days(1.234567898);
  gen_time_span_from_days(12345.678987654);
  gen_time_span_from_days(0.000011574);
  gen_time_span_from_days(0.000694444);
  gen_time_span_from_days(0.041666666);
  gen_time_span_from_days(1);
  gen_time_span_from_days(20.84745602);
}
 
// This example of time_span::from_days(double)
// generates the following output.
//
//             from_days          time_span
//             ---------          ---------
//                 6E-09          00:00:00.0010000
//               1.7E-08          00:00:00.0010000
//           0.000123456          00:00:10.6670000
//           1.234567898        1.05:37:46.6660000
//       12345.678987654    12345.16:17:44.5330000
//            1.1574E-05          00:00:01
//           0.000694444          00:01:00
//           0.041666666          01:00:00
//                     1        1.00:00:00
//           20.84745602       20.20:20:20.2000000

Remarks

The value parameter is converted to milliseconds, which is converted to ticks, and that number of ticks is used to initialize the new xd::time_span. Therefore, value will only be considered accurate to the nearest millisecond. Note that, because of the loss of precision of the Double data type, this conversion can cause an xtd::overflow_exception for values that are near to but still in the range of either xd::time_span::min_value or xd::time_span::max_value. For example, this causes an xtd:overflow_exception in the following attempt to instantiate a xd::time_span object.

// The following throws an overflow_exception at runtime
auto max_span = time_span::from_days(time_span::max_value.total_days());