基于c++的C/S网络通信 从入门到精通（三）

为了实现客户端与服务器的相互通信，这次我们将加入多线程：一个线程发送数据，一个线程接受数据

                   客户端代码如下:

#include <iostream>
#include <winsock2.h>
#pragma comment (lib,"WS2_32.lib")

using namespace std;

SOCKET clientsocket;
HANDLE hMutex;//互斥使用输出窗体
int flag_connect = 1;

DWORD WINAPI Fun_Recv(LPVOID);
DWORD WINAPI Fun_Send(LPVOID);

int main()
{
	//加载套接字库
	WSADATA wsadata;
	int iRet=WSAStartup(MAKEWORD(2, 2), &wsadata);
	if (iRet != 0)
	{
		cout << "套接字库加载失败" << endl;
		return -1;
	}
	else
	{
		cout << "套接字库加载成功" << endl;
	}
	//创建套接字
	clientsocket = socket(AF_INET, SOCK_STREAM, 0);
	if (clientsocket == INVALID_SOCKET)
	{
		cout << "套接字创建失败" << endl;
		return -1;
	}
	else
	{
		cout << "套接字创建成功" << endl;
	}

	//初始化客户端地址族变量
	SOCKADDR_IN addrSrv;
	addrSrv.sin_family = AF_INET;
	addrSrv.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");
	addrSrv.sin_port = htons(8000);

	//连接
	iRet=connect(clientsocket, (SOCKADDR*)&addrSrv, sizeof(SOCKADDR));
	if (iRet == SOCKET_ERROR)
	{
		cout << "连接失败" << endl;
		return -1;
	}
	else
	{
		cout << "连接成功" << endl;
	}

	HANDLE Send_Thread = CreateThread(NULL, 0, Fun_Send, 0, 0, NULL);//创建发送线程
	HANDLE Recv_Thread = CreateThread(NULL, 0, Fun_Recv, 0, 0, NULL);//创建接受线程
	CloseHandle(Send_Thread);//关闭句柄
	CloseHandle(Recv_Thread);//关闭句柄
	hMutex = CreateMutex(NULL, FALSE, L"mutex");//创建互斥量

	while (flag_connect)
	{
		Sleep(100);//必须使用sleep
	}
	return 0;
	
}

DWORD WINAPI Fun_Send(LPVOID)
{
	while (flag_connect)
	{
		char sendBuff[255] ;

		cin >> sendBuff;

		int iRet = send(clientsocket, sendBuff, sizeof(sendBuff), 0);
		if (iRet <= 0)
		{
			cout << "服务器关闭连接" << endl;
			closesocket(clientsocket);
			WSACleanup();
			flag_connect = 0;
			return -1;
		}
	
	}
	return 0;
}

DWORD WINAPI Fun_Recv(LPVOID)
{
	while (flag_connect)
	{
		char recvBuff[255];
		int iRet = recv(clientsocket, recvBuff, 255, 0);
		if (iRet <= 0)
		{
			cout << "服务器关闭连接" << endl;
			closesocket(clientsocket);
			WSACleanup();
			flag_connect = 0;
			return -1;
		}
		cout << recvBuff << endl;
	}
	return 0;
}

               服务器端代码如下：

#include <iostream>
#include <winsock2.h>
#pragma comment (lib,"WS2_32.lib")

using namespace std;

SOCKET connectSocket;
SOCKET serversocket;
HANDLE hMutex;//互斥使用输出窗体
int flag_connect = 1;

DWORD WINAPI Fun_Recv(LPVOID);
DWORD WINAPI Fun_Send(LPVOID);

int main()
{
	//加载套接字库
	WSADATA wsadata;
	int iRet=WSAStartup(MAKEWORD(2, 2), &wsadata);
	if (iRet != 0)
	{
		cout << "套接字库加载失败" << endl;
		return -1;
	}
	//创建套接字
	
	serversocket = socket(AF_INET, SOCK_STREAM, 0);
	if (serversocket == INVALID_SOCKET)
	{
		cout << "套接字创建失败" << endl;
		return -1;
	}
	else
	{
		cout << "套接字创建成功" << endl;
	}
	//初始化服务器地址族变量
	SOCKADDR_IN addrSrv;
	addrSrv.sin_family = AF_INET;
	addrSrv.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");
	addrSrv.sin_port = htons(8000);

	//绑定
	iRet = bind(serversocket, (SOCKADDR*)&addrSrv, sizeof(SOCKADDR));
	if (iRet == SOCKET_ERROR)
	{
		cout << "绑定失败" << endl;
		return -1;
	}
	else
	{
		cout << "绑定成功" << endl;
	}
	//监听
	iRet = listen(serversocket, 10);
	if (iRet == SOCKET_ERROR)
	{
		cout << "开启监听失败" << endl;
		return -1;
	}
	else
	{
		cout << "开启监听成功" << endl;
	}
	//接收连接
	SOCKADDR_IN addrClient;
	int len = sizeof(SOCKADDR);
	connectSocket=accept(serversocket, (SOCKADDR*)&addrClient, &len);
	if (INVALID_SOCKET == connectSocket)
	{
		cout << "接受连接失败" << endl;
		return -1;
	}
	else
	{
		cout << "接受连接成功" << endl;
	}
	//接收数据

	HANDLE Send_Thread = CreateThread(NULL, 0, Fun_Send, 0, 0, NULL);//创建发送线程
	HANDLE Recv_Thread = CreateThread(NULL, 0, Fun_Recv, 0, 0, NULL);//创建接受线程
	CloseHandle(Send_Thread);//关闭句柄
	CloseHandle(Recv_Thread);//关闭句柄
	hMutex = CreateMutex(NULL, FALSE, L"mutex");//创建互斥量

	int i = 0;
	while (flag_connect)
	{
		Sleep(100);//必须使用Sleep
	}
	return 0;
}

DWORD WINAPI Fun_Send(LPVOID)
{
	while (flag_connect)
	{
		char sendBuff[255];
		cin >> sendBuff;
		int iRet = send(connectSocket, sendBuff, sizeof(sendBuff), 0);
		if (iRet <= 0)
		{
			cout << "发送线程关闭连接" << endl;
			flag_connect = 0;
			return -1;
		}
	}
	return 0;
}

DWORD WINAPI Fun_Recv(LPVOID) 
{
	while (flag_connect)
	{
		char recvBuff[255];
		int iRet = recv(connectSocket, recvBuff, 255, 0);
		if (iRet <= 0)
		{
			cout << "接受线程关闭连接" << endl;
			closesocket(serversocket);
			WSACleanup();
			flag_connect = 0;
			return -1;
		}
		cout << recvBuff << endl;
	}
	return 0;
}

问题：如果是多个客户端又该如何实现呢？

打包代码下载地址：阻塞式CS通信