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最新推荐文章于 2025-09-10 15:16:07 发布

iteye_20686

最新推荐文章于 2025-09-10 15:16:07 发布

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CC 4.0 BY-SA版权

文章标签： c/c++

本文链接：https://blog.youkuaiyun.com/iteye_20686/article/details/82446801

本文通过三个示例介绍了如何使用Boost.Asio库来创建同步及异步定时器，并展示了如何利用bind实现周期性的任务调度。

一.同步定时器，如下：

#include <iostream>

#include <boost/asio.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>
int main(int argc,char** argv){
   boost::asio::io_service ios;
   boost::asio::deadline_timert(ios,boost::posix_time::seconds(2));
   std::cout<<t.expires_at()<<std::endl;
   t.wait();
   std::cout<<"helloworld"<<std::endl;
   return 0;

}

二.异步定时器，如下：

#include <iostream>
#include <boost/asio.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>
void print(const boost::system::error_code& e){
   std::cout<<"hello asio"<<std::endl;
}
int main(int argc,char** argv){
   boost::asio::io_service ios;
   boost::asio::deadline_timer t(ios,boost::posix_time::seconds(2));
   t.async_wait(print);
   std::cout<<"it show before texpired."<<std::endl;
   ios.run();
   return 0;
}

#include <iostream>
#include <boost/asio.hpp>
#include <boost/bind.hpp>
#include <boost/function.hpp>
#include <boost/date_time/posix_time/posix_time.hpp>
using namespace boost;
using namespace boost::asio;
void print1(){
std::cout<<"hello asio"<<std::endl;
}
void print2(){
std::cout<<"hello boost"<<std::endl;
}
三.用bind实现异步定时器，如下：

#include <iostream>

#include <boost/asio.hpp>

#include <boost/bind.hpp>

#include <boost/function.hpp>

#include<boost/date_time/posix_time/posix_time.hpp>

using namespace boost;

using namespace boost::asio;
class a_timer{
private:
   int count;
   int count_max;
   function<void()> f;
   deadline_timer t;
public:
   template<typename F>
   a_timer(io_service& ios,int x,Ffunc):f(func),count_max(x),count(0)
       ,t(ios,posix_time::millisec(500))
   {
       t.async_wait(bind(&a_timer::call_func,this,placeholders::error));
   }
   void call_func(const system::error_code& e){
       if(count >= count_max){
           return;
       }
       ++count;
       f();
       t.expires_at(t.expires_at() +posix_time::millisec(500));
       t.async_wait(bind(&a_timer::call_func,this,placeholders::error));
   }
};
int main(int argc,char** argv){
   io_service ios;
   a_timer at1(ios,5,print1);
   a_timer at2(ios,5,print2);
   ios.run();
   return 0;
}