版权声明:本文为博主原创文章,未经博主允许不得转载。 https://blog.csdn.net/DumpDoctorWang/article/details/81781227
一、缘起
做的一些项目需要计时,但是网上找到的计时博客比较老,或者互相copy,或者不跨平台。其实C++11中的chrono库,就是可以用来写计时器,跨平台,跨编译器,下面就是计时器的实现
//timer.h
#ifndef W_TIMER_H
#define W_TIMER_H
#include <iostream>
#include <string>
#include <chrono>
class Timer {
public:
explicit Timer() {
_name = "Time elapsed:";
restart();
}
explicit Timer(const std::string &name) {
_name = name + ":";
restart();
}
/**
* 启动计时
*/
inline void restart() {
_start_time = std::chrono::steady_clock::now();
}
/**
* 结束计时
* @return 返回ms数
*/
inline double elapsed(bool restart = false) {
_end_time = std::chrono::steady_clock::now();
std::chrono::duration<double> diff = _end_time-_start_time;
if(restart)
this->restart();
return diff.count()*1000;
}
/**
* 打印时间并重启计时器
* @param tip 提示
*/
void rlog(const std::string &tip){
log(true,tip,true,false);
}
/**
* 打印时间
* @param reset 输出之后是否重启计时器,true重启,false不重启
* @param unit_ms true是ms,false是s
* @param tip 输出提示
* @param kill 输出之后是否退出程序,true退出,false不退出
*/
void log(bool reset = false, const std::string &tip = "",
bool unit_ms = true, bool kill = false
) {
if (unit_ms) {
if (tip.length() > 0)
std::cout << tip+":" << elapsed() << "ms" << std::endl;
else
std::cout << _name << elapsed() << "ms" << std::endl;
} else {
if (tip.length() > 0)
std::cout << tip+":" << elapsed() / 1000.0 << "s" << std::endl;
else
std::cout << _name << elapsed() / 1000.0 << "s" << std::endl;
}
if (reset)
this->restart();
if (kill)
exit(5);
}
private:
std::chrono::steady_clock::time_point _start_time;
std::chrono::steady_clock::time_point _end_time;
std::string _name;
}; // timer
#endif //W_TIMER_H
二、使用实例
#include <iostream>
#include "timer.h"
#include <unistd.h> //LINUX 头文件
int main() {
std::cout << "Hello, World!" << std::endl;
Timer timer;
sleep(1);//休眠1s,Windows里,休眠函数为Sleep(),头文件是windows.h
std::cout<<timer.elapsed()<<std::endl;
timer.restart();
sleep(1);//休眠1s
timer.rlog("时间");
return 0;
}