start()

void xtd::diagnostics::stopwatch::start ( )

noexcept

Starts, or resumes, measuring elapsed time for an interval.

Remarks

In a typical xtd::diagnostics::stopwatch scenario, you call the xtd::diagnostics::stopwatch::start method, then eventually call the xtd::diagnostics::stopwatch::stop method, and then you check elapsed time using the xtd::diagnostics::stopwatch::elapsed property.

Once started, a xtd::diagnostics::stopwatch timer measures the current interval, in elapsed timer ticks, until the instance is stopped or reset. starting a xtd::diagnostics::stopwatch that is already running does not change the timer state or reset the elapsed time properties.

When a stopwatch instance measures more than one interval, the start method resumes measuring time from the current elapsed time value. A stopwatch instance calculates and retains the cumulative elapsed time across multiple time intervals, until the instance is reset. Use the reset method before calling start to clear the cumulative elapsed time in a stopwatch instance. Use the restart method to reset and start the stopwatch with a single command.

Examples

The following example initializes a xtd::diagnostics::stopwatch instance by using a simple class constructor.

#include <xtd/diagnostics/stopwatch>
#include <xtd/threading/thread>
#include <xtd/console>
#include <chrono>
 
using namespace std::chrono;
using namespace xtd;
using namespace xtd::threading;
 
auto main() -> int {
  auto stopwatch = xtd::diagnostics::stopwatch {};
  stopwatch.start();
  thread::sleep(10000_ms);
  stopwatch.stop();
  // Get the elapsed time as a duration value.
  auto ts = stopwatch.elapsed();
  
  // Format and display the duration value.
  auto elapsed_time = string::format("{0:H}:{0:M}:{0:S}.{1:D2}", ts, ts.milliseconds() / 10);
  console::write_line("RunTime " + elapsed_time);
}
 
// This code produces the following output :
//
// RunTime 00:00:10.00

Examples

lcd_label2.cpp, and stopwatch_constructor.cpp.