TCP/IP是当下网络协议栈中的主流协议 TCP属于传输层的协议 可靠传输 包括经典的三次握手等等
IP协议是网络层协议 尽全力传输但不可靠 学过计算机网络的同学们对这个应该比较熟悉
以下是使用C++进行网络通信的实例
服务端
主要使用多线程技术建立连接 也就是一个服务端可以连接多个客户端 最大连接数可以限定
向客户端发送字符串this is server 并启动一个线程等待客户端发送信息过来
如果客户端发送A过来 服务器返回B 发送C过来 服务器返回D 发送exit之后服务器关闭线程
效果图如下
代码如下
#include<iostream> #include<stdlib.h> #include<WinSock2.h> #define _WINSOCK_DEPRECATED_NO_WARNINGS using namespace std; #pragma comment(lib, "ws2_32.lib") DWORD WINAPI threadpro(LPVOID pParam) { SOCKET hsock = (SOCKET)pParam; char buffer[1024]; char sendBuffer[1024]; if (hsock != INVALID_SOCKET) cout << "start receive" << endl; while (1) { int num = recv(hsock, buffer, 1024, 0); if (num >= 0) cout << "receive from clinet" << buffer << endl; if (!strcmp(buffer, "A")) { memset(sendBuffer, 0, 1024); strcpy_s(sendBuffer, "B"); int ires = send(hsock, sendBuffer, sizeof(sendBuffer), 0);//回送信息 cout << "send to client" << sendBuffer << endl; } else if (!strcmp(buffer, "C")) { memset(sendBuffer, 0, 1024); strcpy_s(sendBuffer, "D"); int ires = send(hsock, sendBuffer, sizeof(sendBuffer), 0);//回送信息 cout << "send to client" << sendBuffer << endl; } else if (!strcmp(buffer, "exit")) { cout << "client close" << endl; cout << "server process close" << endl; return 0; } else { memset(sendBuffer, 0, 1024); strcpy_s(sendBuffer, "ERR"); int ires = send(hsock, sendBuffer, sizeof(sendBuffer), 0);//回送信息 cout << "send to client" << sendBuffer << endl; } } return 0; } void main() { WSADATA wsd; WSAStartup(MAKEWORD(2, 2), &wsd); SOCKET m_SockServer; sockaddr_in serveraddr; sockaddr_in serveraddrfrom; SOCKET m_Server[20]; serveraddr.sin_family = AF_INET; serveraddr.sin_port = htons(4600);//端口号 //serveraddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1"); m_SockServer = socket(AF_INET, SOCK_STREAM, 0); int i = bind(m_SockServer, (sockaddr*)&serveraddr, sizeof(serveraddr));//绑定数 cout << "bind:" << i << endl; int imaxconnect = 20; int iconnect = 0; int ilisret; char buf[] = "this is server\0"; char WarnBuf[] = "it is over max connect\0"; int len = sizeof(sockaddr); while (1) { ilisret = listen(m_SockServer, 0); m_Server[iconnect] = accept(m_SockServer, (sockaddr*)&serveraddrfrom, &len); if (m_Server[iconnect] != INVALID_SOCKET) { int ires = send(m_Server[iconnect], buf, sizeof(buf), 0); cout << "accept:" << ires << endl; iconnect++; if (iconnect > imaxconnect) { int ires = send(m_Server[iconnect], WarnBuf, sizeof(WarnBuf), 0); } else { HANDLE m_handle; DWORD nThreadld = 0; m_handle = (HANDLE)::CreateThread(NULL, 0, threadpro, (LPVOID)m_Server[--iconnect], 0, &nThreadld);//启动 线程 } } WSACleanup(); } }
客户端
#include<iostream> #include<stdlib.h> #include"winsock2.h" #include<time.h> #define _WINSOCK_DEPRECATED_NO_WARNINGS using namespace std; #pragma comment(lib,"ws2_32.lib") void main() { WSADATA wsd; WSAStartup(MAKEWORD(2, 2), &wsd); SOCKET m_SockClient; sockaddr_in clientaddr; clientaddr.sin_family = AF_INET; clientaddr.sin_port = htons(4600); //clientaddr.sin_addr.S_un.S_addr =inet_addr("127.0.0.1"); m_SockClient = socket(AF_INET, SOCK_STREAM, 0); int i = connect(m_SockClient, (sockaddr*)&clientaddr, sizeof(clientaddr)); cout << "connect" << i << endl; char buffer[1024]; char inBuf[1024]; int num; num = recv(m_SockClient, buffer, 1024, 0); if (num > 0) { cout << "receive from server" << buffer << endl; while (1) { num = 0; cin >> inBuf; if (!strcmp(inBuf, "exit")) { send(m_SockClient, inBuf, sizeof(inBuf), 0); return; } send(m_SockClient, inBuf, sizeof(inBuf), 0); num = recv(m_SockClient, buffer, 1024, 0); if (num >= 0) cout << "reveive from server" << buffer << endl; } } }
