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

 

C++

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std::chrono::duration

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treat_as_floating_point duration_values

 

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

转换时长到另一个拥有不同嘀嗒间隔的时长 (函数模板)