from_hours() [1/2]

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

static

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

Parameters

value

A number of hours, 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.

Remarks

The value parameter is converted to milliseconds, which is converted to ticks, and that number of ticks is used to initialize the new xtd::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 generate an xtd::overflow_exception for values that are near to but still in the range of either xtd::time_span::min_value or xtd::time_span::max_value. For example, this causes an xtd::overflow_exception in the following attempt to instantiate a xtd::time_span object.

// The following throws an overflow_exception at runtime
auto max_span = time_span::from_hours(time_span::max_value::total_hours());

Examples

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

#include <xtd/console>
#include <xtd/time_span>
#include <xtd/int64_object>
#include <xtd/string>
 
using namespace xtd;
 
void gen_time_span_from_hours(double hours) {
  // Crée un objet time_span et une chaîne string à partir
  // d'un nombre d'heures.
  time_span interval = time_span::from_hours(hours);
  string timeInterval = interval.to_string();
  
  // Remplit la fin de la chaîne string avec des espaces si elle
  // ne contient pas de millisecondes.
  size_t pIndex = timeInterval.index_of(':');
  pIndex = timeInterval.index_of( '.', pIndex );
  if (pIndex < 0) timeInterval += "        ";
  
  console::write_line( "{0,21}{1,26}", hours, timeInterval );
}
 
int main( ) {
  console::write_line("This example of time_span::from_hours(double)\n"
                      "generates the following output.\n" );
  console::write_line( "{0,21}{1,19}",
                      "from_hours", "time_span" );
  console::write_line( "{0,21}{1,19}",
                      "----------", "---------" );
  
  gen_time_span_from_hours( 0.0000002 );
  gen_time_span_from_hours( 0.0000003 );
  gen_time_span_from_hours( 0.0012345 );
  gen_time_span_from_hours( 12.3456789 );
  gen_time_span_from_hours( 123456.7898765 );
  gen_time_span_from_hours( 0.0002777 );
  gen_time_span_from_hours( 0.0166666 );
  gen_time_span_from_hours( 1 );
  gen_time_span_from_hours( 24 );
  gen_time_span_from_hours( 500.3389445 );
}
 
// This example of time_span::from_hours(double)
// generates the following output.
//
//            from_hours          time_span
//            ----------          ---------
//                 2E-07          00:00:00.0007200
//                 3E-07          00:00:00.0010800
//             0.0012345          00:00:04.4442000
//            12.3456789          12:20:44.4440400
//        123456.7898765     5144.00:47:23.5554000
//             0.0002777          00:00:00.9997199
//             0.0166666          00:00:59.9997600
//                     1                  01:00:00
//                    24                1.00:00:00
//           500.3389445       20.20:20:20.2002000