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我學習了C++，現在我想繼續學習一些網絡編程。我決定使用boost :: asio，因爲它是多平臺的。我寫了這個簡單的程序：boost :: asio爲每個客戶端分開的陣列
客戶端：
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <boost/asio.hpp>
using boost::asio::ip::tcp;
enum { max_length = 1000000 };
int main(int argc, char* argv[])
{
while(1)
{
try
{
if (argc != 3)
{
std::cerr << "Usage: blocking_tcp_echo_client <host> <port>\n";
return 1;
}
boost::asio::io_service io_service;
tcp::resolver resolver(io_service);
tcp::resolver::query query(tcp::v4(), argv[1], argv[2]);
tcp::resolver::iterator iterator = resolver.resolve(query);
tcp::socket s(io_service);
s.connect(*iterator);
using namespace std; // For strlen.
std::cout << "Enter message: ";
char request[max_length];
std::cin.getline(request, max_length);
if (request == "\n")
continue;
size_t request_length = strlen(request);
boost::asio::write(s, boost::asio::buffer(request, request_length));
char reply[max_length];
boost::system::error_code error;
size_t reply_length = s.read_some(boost::asio::buffer(reply), error);
if (error == boost::asio::error::eof)
break; // Connection closed cleanly by peer.
else if (error)
throw boost::system::system_error(error); // Some other error.
std::cout << "Reply is: ";
std::cout.write(reply, reply_length);
std::cout << "\n";
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
exit(1);
}
}
return 0;
}
服務器：
#include <cstdlib>
#include <iostream>
#include <boost/bind.hpp>
#include <boost/smart_ptr.hpp>
#include <boost/asio.hpp>
#include <boost/thread.hpp>
#include <boost/regex.hpp>
#include <boost/lexical_cast.hpp>
#include <string>
using boost::asio::ip::tcp;
const int max_length = 1000000;
std::string user_array[100];
typedef boost::shared_ptr<tcp::socket> socket_ptr;
unsigned short analyze_user_request(std::string& user_request, short unsigned* ID, std::string* request_value)
{
// function returns:
// 0: if user request is incorrect
// 1: if user requests "PUT" operation
// 2: if user requests "GET" operation
// Furthermore, if request is correct, its value (i.e. ID number and/or string) is saved to short unsigned and string values passed by pointers.
boost::regex exp("^[[:space:]]*(PUT|GET)[[:space:]]+([[:digit:]]{1,2})(?:[[:space:]]+(.*))?$");
boost::smatch what;
if (regex_match(user_request, what, exp, boost::match_extra))
{
short unsigned id_number = boost::lexical_cast<short unsigned>(what[2]);
if (what[1] == "PUT")
{
boost::regex exp1("^[a-zA-Z0-9]+$");
std::string value = boost::lexical_cast<std::string>(what[3]);
if (value.length() > 4095)
return 0;
if (!regex_match(value, exp1))
return 0;
else
{
*request_value = value;
*ID = id_number;
return 1;
}
}
if (what[1] == "GET")
{
*ID = id_number;
return 2;
}
}
if (!regex_match(user_request, what, exp, boost::match_extra))
return 0;
}
void session(socket_ptr sock)
{
try
{
for (;;)
{
char data[max_length];
boost::system::error_code error;
size_t length = sock->read_some(boost::asio::buffer(data), error);
if (error == boost::asio::error::eof)
break; // Connection closed cleanly by peer.
else if (error)
throw boost::system::system_error(error); // Some other error.
// convert buffer data to string for further procession
std::string line(boost::asio::buffers_begin(boost::asio::buffer(data)), boost::asio::buffers_begin(boost::asio::buffer(data)) + length);
std::string reply; // will be "QK", "INVALID", or "OK <value>"
unsigned short vID;
unsigned short* ID = &vID;
std::string vrequest_value;
std::string* request_value = &vrequest_value;
unsigned short output = analyze_user_request(line, ID, request_value);
if (output == 1)
{
// PUT
reply = "OK";
user_array[*ID] = *request_value;
}
else if (output == 2)
{
// GET
reply = user_array[*ID];
if (reply == "")
reply = "EMPTY";
}
else
reply = "INVALID";
boost::system::error_code ignored_error;
size_t ans_len=reply.length();
boost::asio::write(*sock, boost::asio::buffer(reply));
}
}
catch (std::exception& e)
{
std::cerr << "Exception in thread: " << e.what() << "\n";
}
}
void server(boost::asio::io_service& io_service, short port)
{
tcp::acceptor a(io_service, tcp::endpoint(tcp::v4(), port));
for (;;)
{
socket_ptr sock(new tcp::socket(io_service));
a.accept(*sock);
boost::thread t(boost::bind(session, sock));
}
}
int main(int argc, char* argv[])
{
try
{
if (argc != 2)
{
std::cerr << "Usage: blocking_tcp_echo_server <port>\n";
return 1;
}
boost::asio::io_service io_service;
using namespace std; // For atoi.
server(io_service, atoi(argv[1]));
}
catch (std::exception& e)
{
std::cerr << "Exception: " << e.what() << "\n";
}
return 0;
}
基本上，它是允許用戶將數據存儲在服務器上的應用程序。用戶可以使用PUT命令插入新數據，然後輸入ID號和數據值，然後使用GET命令，然後使用ID檢索數據。用戶請求在analyze_user_request函數中處理，隨後寫入或讀取數組。問題是，現在所有的客戶都在使用相同的全球架構。這意味着，如果一個客戶端將某些東西保存在特定ID下，所有其他客戶端都可以讀取它，因爲它們訪問相同的數組我想知道，如何將數組與不同的客戶端關聯起來，並在新客戶端連接時創建一個新數組？
如何在一個類中封裝客戶端？ – netcoder