我在C ++中使用简单的Winsock聊天应用程序时遇到问题。我编写了一个代码，使用户可以选择是否要发送数据或接收数据，并根据用户的选择，执行相应的功能。我想要实现的是，用户可以同时发送和接收数据。我怎么能接近它？请注意，我不想使用多个客户端，我只想通过服务器发送和接收数据，并同时通过客户端发送和接收数据。
编辑：我添加了我的代码。
#include <WinSock2.h>
#include <Windows.h>
#include <iostream>
#include <string>
#include <stdio.h>
#include <ctime>
int main()
{
string IP;
int userType;
// Ask the user if he is server or client
cout << "Hi, which type of user are you? 1 - Server, 2 - Client" <<endl;
cin >> userType;
// depending on the declared user type, execute the appropriate code
if (userType == 1)
{
//initialize winsock and create a socket
WSAData wsaData; // initialize
iResult = WSAStartup(MAKEWORD(2,1), &wsaData);
if (iResult != NO_ERROR) // check for errors
cout << "Error at WSAStartup()" <<endl;
else
cout << "WSAStartup() is OK." <<endl;
// create socket
sockSocket = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); // create a socket
if (sockSocket == INVALID_SOCKET) // check for errors
{
cout << "Error at socket(): " << WSAGetLastError();
WSACleanup();
return true;
}
else
cout << "Socket() is OK." <<endl;
return true;
// bind to socket
service.sin_addr.s_addr = inet_addr("0.0.0.0");
service.sin_family = AF_INET;
service.sin_port = htons(55555);
if (bind(sockSocket, (SOCKADDR*)&service, sizeof(service)) == SOCKET_ERROR) // cheking for errors
{
cout << "Bind() failed." << endl;
closesocket(sockSocket);
return true;
}
else
cout << "Bind() is OK." <<endl;
// listen
listen(sockSocket, SOMAXCONN);
if (listen(sockSocket, 10) == SOCKET_ERROR) // check for errors
{
cout << "Error listening on socket." << endl;
return true;
}
else
cout << "Listen() is OK." <<endl;
//accept connection
servlen = sizeof(service);
cout << "Waiting for user to connect..." << endl;
acceptSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if(acceptSocket = accept(sockSocket, (SOCKADDR*)&service, &servlen))
{
cout << "A coonnection was found" <<endl<<endl;
}
sockSocket = acceptSocket;
// receive messages
do
{
std::string message;
char Buffer[512];
iResult = recv(sockSocket, Buffer, 512, 0);
Buffer[iResult] = '\0';
message = Buffer;
currentDate();
std::cout << Buffer <<endl<<endl;
}while(iResult>0);
closesocket(sockSocket);
WSACleanup();
}
else if (userType == 2)
{
// exactly the same code as for server part to initialize and create socket
// ask for the ip the user wants to connect to
cout << "Hi what's the IP that you want to connect to?" <<endl;
cin >> IP;
// connect to socket
conService.sin_addr.s_addr = inet_addr(IP); // connect to the ipnuted IP
conService.sin_family = AF_INET;
conService.sin_port = htons(55555); // should the port also be the argument?
if (connect(sockSocket, (SOCKADDR*)&conService, sizeof(conService)) == SOCKET_ERROR) // check for errors
{
cout << "Failed to connect: " << WSAGetLastError();
WSACleanup();
return true;
}
else
{
cout << "Connected." <<endl;
}
// send messages
for (;;)
{
std::string message;
std::getline(std::cin, message);
unsigned int Length = strlen(message.c_str());
if(Length>512)
Length = 512;
currentDate();
iResult = send(sockSocket, message.c_str(),Length,0);
}
closesocket(sockSocket);
WSACleanup();
}
WSACleanup();
return 0;
}
Edit2：正如Lemy在评论中所建议的，我需要有第二个线程（因为第一个线程就是主函数中发生的事情）。根据我的理解，我可以使用CreateThread函数。解决了如何发送和接收消息的问题（我应该创建另一个线程），但现在我遇到了实现解决方案的问题。正如我在Lemy的回答下面的评论中所写，我得到的错误是指我使用CreateThread函数的行（HANDLE hThread = CreateThread（0,0，＆amp; ReadingThread，acceptSocket，0，＆amp; dwThreadID）;）：
有任何提示吗？希望这会使我的问题更具体（如果不是请告诉我应该指定更多的内容）。
答案 0 :(得分：5)
您需要让客户端和服务器在后台连续读取连接的生命周期，然后他们可以在需要时并行发送数据。将您的阅读逻辑移动到一个单独的线程中，例如：
#include <WinSock2.h>
#include <Windows.h>
#include <iostream>
#include <string>
#include <stdio.h>
#include <ctime>
DWORD WINAPI ReadingThread(LPVOID param)
{
SOCKET s = (SOCKET) param;
char Buffer[512];
int iResult;
do
{
iResult = recv(s, Buffer, 512, 0);
if (iResult <= 0) break;
Buffer[iResult] = '\0';
std::cout << "Recv: " << message << std::endl;
}
while (true);
return 0;
}
int main()
{
int userType;
HANDLE hThread;
DWORD dwThreadID;
//initialize winsock and create a socket
WSAData wsaData; // initialize
iResult = WSAStartup(MAKEWORD(2,1), &wsaData);
if (iResult != NO_ERROR) // check for errors
{
std::cout << "Error at WSAStartup()" << std::endl;
return 0;
}
std::cout << "WSAStartup() is OK." << std::endl;
// Ask the user if he is server or client
std::cout << "Hi, which type of user are you? 1 - Server, 2 - Client" << std::endl;
std::cin >> userType;
// depending on the declared user type, execute the appropriate code
if (userType == 1)
{
// create socket
sockSocket = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); // create a socket
if (sockSocket == INVALID_SOCKET) // check for errors
{
std::cout << "Error at socket(): " << WSAGetLastError() << std::endl;
WSACleanup();
return 0;
}
std::cout << "Socket() is OK." << std::endl;
// bind to socket
service.sin_addr.s_addr = INADDR_ANY;
service.sin_family = AF_INET;
service.sin_port = htons(55555);
if (bind(sockSocket, (SOCKADDR*)&service, sizeof(service)) == SOCKET_ERROR) // cheking for errors
{
std::cout << "Error at bind(): " << WSAGetLastError() << std::endl;
closesocket(sockSocket);
WSACleanup();
return 0;
}
std::cout << "Bind() is OK." << std::endl;
// listen
if (listen(sockSocket, 10) == SOCKET_ERROR) // check for errors
{
std::cout << "Error at listen(): " << WSAGetLastError() << std::endl;
closesocket(sockSocket);
WSACleanup();
return 0;
}
std::cout << "Listen() is OK." << std::endl;
//accept connection
servlen = sizeof(service);
std::cout << "Waiting for user to connect..." << std::endl;
acceptSocket = accept(sockSocket, (SOCKADDR*)&service, &servlen);
if (acceptSocket != INVALID_SOCKET)
{
std::cout << "Error at accept(): " << WSAGetLastError() << std::endl;
closesocket(sockSocket);
WSACleanup();
return 0;
}
std::cout << "A client has connected" << std::endl << std::endl;
// receive messages
hThread = CreateThread(NULL, 0, &ReadingThread, (void*)acceptSocket, 0, &dwThreadID);
if (!hThread)
{
std::cout << "Error at CreateThread(): " << GetLastError() << std::endl;
closesocket(acceptSocket);
closesocket(sockSocket);
WSACleanup();
return 0;
}
// send messages
do
{
std::string message;
if (!std::getline(std::cin, message))
break;
if (send(acceptSocket, msg.c_str(), msg.length(), 0) == SOCKET_ERROR)
{
std::cout << "Error at send(): " << WSAGetLastError() << std::endl;
break;
}
}
while (true);
closesocket(acceptSocket);
WaitForSingleObject(hThread, INFINITE);
CloseHandle(hThread);
closesocket(sockSocket);
WSACleanup();
}
else if (userType == 2)
{
// create socket
sockSocket = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); // create a socket
if (sockSocket == INVALID_SOCKET) // check for errors
{
std::cout << "Error at socket(): " << WSAGetLastError() << std::endl;
WSACleanup();
return 0;
}
std::cout << "Socket() is OK." << std::endl;
// ask for the ip the user wants to connect to
std::string IP;
std::cout << "Hi what's the IP that you want to connect to?" << std::endl;
std::cin >> IP;
// connect to socket
conService.sin_addr.s_addr = inet_addr(IP.c_str()); // connect to the ipnuted IP
conService.sin_family = AF_INET;
conService.sin_port = htons(55555); // should the port also be the argument?
if (connect(sockSocket, (SOCKADDR*)&conService, sizeof(conService)) == SOCKET_ERROR) // check for errors
{
std::cout << "Failed to connect: " << WSAGetLastError() << std::endl;
closesocket(sockSocket);
WSACleanup();
return 0;
}
std::cout << "Connected." << std::endl;
// receive messages
hThread = CreateThread(NULL, 0, &ReadingThread, (void*)sockSocket, 0, &dwThreadID);
if (!hThread)
{
std::cout << "Error at CreateThread(): " << GetLastError() << std::endl;
closesocket(sockSocket);
WSACleanup();
return 0;
}
// send messages
do
{
std::string message;
if (!std::getline(std::cin, message))
break;
if (send(sockSocket, msg.c_str(), msg.length(), 0) == SOCKET_ERROR)
{
std::cout << "Error at send(): " << WSAGetLastError() << std::endl;
break;
}
}
while (true);
closesocket(sockSocket);
WaitForSingleObject(hThread, INFINITE);
CloseHandle(hThread);
WSACleanup();
}
else
{
std::cout << "Invalid type entered!" << std::endl;
WSACleanup();
return 0;
}
return 0;
}