由于asio服务端需要在一个线程中启动异步操作,即一个死循环等待socket事件,因此需要创建一个线程,这里使用QT的线程支持即可.创建QThread的子类,重写其run()虚函数,在里面调用io_service::run();在将asio自带的tcp异步echo服务代码全部移植过来,测试通过.

//asiotcpserverthread.h头文件,其中声明了线程类及从控制台范例中移植过来的类

#ifndef ASIOTCPSERVERTHREAD
#define ASIOTCPSERVERTHREAD

//asio
#include <boost/asio/buffer.hpp>
#include <boost/asio/io_service.hpp>
#include <boost/asio/ip/address.hpp>
#include <boost/asio/ip/address_v4.hpp>
#include <boost/asio/ip/address_v6.hpp>
#include <boost/asio/ip/basic_endpoint.hpp>
#include <boost/asio/ip/basic_resolver.hpp>
#include <boost/asio/ip/basic_resolver_entry.hpp>
#include <boost/asio/ip/basic_resolver_iterator.hpp>
#include <boost/asio/ip/basic_resolver_query.hpp>
#include <boost/asio/ip/host_name.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <boost/asio/write.hpp>
#include <boost/asio/read.hpp>
#include <boost/asio/impl/connect.hpp>
#include <boost/asio/read_until.hpp>
#include <boost/asio/streambuf.hpp>
#include <boost/bind.hpp>
#include <boost/asio/placeholders.hpp>
//qt
#include <QThread>

using boost::asio::ip::tcp;

class AsioTcpServerThread : public QThread
{
public:
 AsioTcpServerThread(void);
 ~AsioTcpServerThread(void);
protected:
 void run();
};

class session
{
public:
 session(boost::asio::io_service& io_service);
 tcp::socket& socket();
 void start();
private:
 void handle_read(const boost::system::error_code& error, size_t bytes_transferred);
 void handle_write(const boost::system::error_code& error);

 tcp::socket socket_;
 enum {max_length = 1024};
 char data_[max_length];
};

class server
{
public:
 server(boost::asio::io_service& io_service, short port);
private:
 void start_accept();
 void handle_accept(session* new_session, const boost::system::error_code& error);

 boost::asio::io_service& io_service_;
 tcp::acceptor acceptor_;
};

const int port = 10800;
#endif

//asiotcpserverthread.cpp  线程类及移植类的实现

#include "asiotcpserverthread.h"

AsioTcpServerThread::AsioTcpServerThread()
{
}

AsioTcpServerThread::~AsioTcpServerThread()
{
}

void AsioTcpServerThread::run()
{
 try
 {
  boost::asio::io_service io_service;
  server s(io_service, port);
  io_service.run();
 }
 catch(std::exception& e)
 {
  
 }
}

session::session(boost::asio::io_service& io_service) : socket_(io_service)
{

}

tcp::socket& session::socket()
{
 return socket_;
}

void session::start()
{
 socket_.async_read_some(boost::asio::buffer(data_, max_length), 
  boost::bind(&session::handle_read, this, 
  boost::asio::placeholders::error, 
  boost::asio::placeholders::bytes_transferred));//异步读取完毕后调用handle_read函数
}

void session::handle_read(const boost::system::error_code& error, size_t bytes_transferred)
{
 if(!error)
 {
  boost::asio::async_write(socket_, 
   boost::asio::buffer(data_, bytes_transferred),
   boost::bind(&session::handle_write, this, boost::asio::placeholders::error));//写完毕后调用handle_write函数
 }
 else
 {
  delete this;
 }
}

void session::handle_write(const boost::system::error_code &error)
{
 if(!error)
 {
  socket_.async_read_some(boost::asio::buffer(data_, max_length),
   boost::bind(&session::handle_read, this,
    boost::asio::placeholders::error,
    boost::asio::placeholders::bytes_transferred));
 }
 else
 {
  delete this;
 }
}

server::server(boost::asio::io_service &io_service, short port)
  : io_service_(io_service), acceptor_(io_service, tcp::endpoint(tcp::v4(), port))
{
 start_accept();
}

void server::start_accept()
{
 session* new_session = new session(io_service_);
 acceptor_.async_accept(new_session->socket(),
  boost::bind(&server::handle_accept, this, new_session,
  boost::asio::placeholders::error));
}

void server::handle_accept(session *new_session, const boost::system::error_code &error)
{
 if(!error)
 {
  new_session->start();
 }
 else
 {
  delete new_session;
 }
 start_accept();
}

//界面头文件

#ifndef QT_BOOST_SERVER_H
#define QT_BOOST_SERVER_H

#include <QtGui/QMainWindow>
#include "ui_qt_boost_server.h"
#include "asiotcpserverthread.h"

class qt_boost_server : public QMainWindow
{
 Q_OBJECT

public:
 qt_boost_server(QWidget *parent = 0, Qt::WFlags flags = 0);
 ~qt_boost_server();

private:
 Ui::qt_boost_serverClass ui;
 AsioTcpServerThread *tcpServer;

private slots:
 void pbStartServerClicked();

};

#endif // QT_BOOST_SERVER_H

//界面实现类 点击按钮启动线程

#include "qt_boost_server.h"

qt_boost_server::qt_boost_server(QWidget *parent, Qt::WFlags flags)
 : QMainWindow(parent, flags)
{
 ui.setupUi(this);
 connect(ui.pbStartServer, SIGNAL(clicked()), this, SLOT(pbStartServerClicked()));
 tcpServer = new AsioTcpServerThread();
}

qt_boost_server::~qt_boost_server()
{

}

void qt_boost_server::pbStartServerClicked()
{
 tcpServer->start();
}