需要包含的头文件及类实现：

#include <chrono>
#include <thread>

class Timer {
public:
    Timer() : m_StartTimepoint(std::chrono::high_resolution_clock::now()) {}

    ~Timer() {
        Stop();
    }

    void Stop() {
        auto endTimepoint = std::chrono::high_resolution_clock::now();

        auto start = std::chrono::time_point_cast<std::chrono::nanoseconds>(m_StartTimepoint).time_since_epoch().count();
        auto end = std::chrono::time_point_cast<std::chrono::nanoseconds>(endTimepoint).time_since_epoch().count();

        auto duration = end - start;
        double ms = duration * 1.0e-6;

        std::cout << duration << "ns (" << ms << "ms)\n";
    }

private:
    std::chrono::time_point<std::chrono::high_resolution_clock> m_StartTimepoint;
};

使用：

int main() {

    //第一个示例
    {
        printf("test1\n");
        Timer timer;
        // 你需要计时的代码
        for (int i = 0; i < 100; i++) {
            std::cout << "Hello, World!\n";
        }
    }

    //第二个示例
    {
        printf("test2\n");
        Timer timer;
        //std::this_thread::sleep_for(std::chrono::seconds(3)); //休眠三秒
        std::this_thread::sleep_for(std::chrono::milliseconds(100)); //休眠100毫秒
    }


    return 0;
}

结果：