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<=> (until C++20)(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)
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common_type treat_as_floating_point      duration_values	formatter<std::chrono::duration> (C++20) hash<std::chrono::duration> (C++26)

 

constexpr rep count() const;		(since C++11)

返回此 duration 的 tick 数。

参数

(无)

返回值

此 duration 的 tick 数。

示例

运行此代码

#include <chrono>
#include <iostream>
 
int main()
{
    std::chrono::milliseconds ms{3}; // 3 milliseconds
    // 6000 microseconds constructed from 3 milliseconds
    std::chrono::microseconds us = 2 * ms;
    // 30Hz clock using fractional ticks
    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

参见

duration_cast (C++11)

将 duration 转换为具有不同 tick 间隔的另一个 duration (函数模板)