std::chrono::duration<Rep,Period>::count

 

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std::chrono::duration

成员函数
duration::duration
duration::operator=
duration::count
duration::zero
duration::min
duration::max
duration::operator+duration::operator-
duration::operator++duration::operator--
duration::operator+=duration::operator-=duration::operator*=duration::operator/=duration::operator%=
非成员函数
operator+operator-operator*operator/operator% operator==operator!=operator<operator<=operator>operator>=operator<=> (C++20 前)(C++20) operator<< (C++20)	duration_cast floor (C++17) ceil (C++17) round (C++17) abs (C++17) operator""h (C++14) operator""min (C++14) operator""s (C++14) operator""ms (C++14) operator""us (C++14) operator""ns (C++14) from_stream (C++20)
辅助类
common_type treat_as_floating_point duration_values formatter<std::chrono::duration> (C++20)

 

constexpr rep count() const;

返回此 duration 的计次数。

参数

（无）

返回值

此 duration 的计次数。

示例

运行此代码

#include <chrono>
#include <iostream>
int main()
{
    std::chrono::milliseconds ms{3}; // 3 毫秒
    // 从 3 毫秒构造 6000 微秒
    std::chrono::microseconds us = 2*ms;
    // 使用分数计次的 30Hz 时钟
    std::chrono::duration<double, std::ratio<1, 30>> hz30(3.5);
 
    std::cout <<  "3 ms duration has " << ms.count() << " ticks\n"
              <<  "6000 us duration has " << us.count() << " ticks\n"
              <<  "3.5 30Hz duration has " << hz30.count() << " ticks\n";       
}

输出：

3 ms duration has 3 ticks
6000 us duration has 6000 ticks
3.5 30Hz duration has 3.5 ticks

参阅

duration_cast (C++11)

转换时长到另一个拥有不同嘀嗒间隔的时长 (函数模板)