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;
}
}
}