C/C++使用Socket通信UDP

接收端

#include <stdio.h>
#include <WinSock2.h>

#pragma comment(lib,"WS2_32.lib")

int main(void)
{
    WSADATA wsd;    // 初始化Socket的变量
    SOCKET s;        // 用于通信的Socket句柄
    SOCKADDR_IN sRecvAddr,sSendAddr;    // 分别为接收地址和发送地址
    USHORT uPort = 1401;                // 通信端口
    CHAR szBuf[1024] = { 0 };            // 通信数据缓冲区
    int nBufLen = 1024,nResult = 0, nSenderAddrSize = sizeof(sSendAddr);

    // 初始化Socket2.2版本
    nResult = WSAStartup(MAKEWORD(2, 2), &wsd);
    if (nResult != NO_ERROR)
    {
        printf("WSAStartup failed:%d
", WSAGetLastError());
        return 1;
    }

    // 创建一个Socket,SOCK_DGRAM表示UDP类型
    s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if (s == INVALID_SOCKET)
    {
        printf("socket failed:%d
", WSAGetLastError());
        return 1;
    }

    // 填充Socket接口
    sRecvAddr.sin_family = AF_INET;        // 地址协议,AF_INET支持TCP和UDP
    sRecvAddr.sin_port = htons(uPort);    // 通信端口,htons转为网络字节顺序
    sRecvAddr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);    // 接收任意地址数据

    // 绑定Socket至本机
    nResult = bind(s, (SOCKADDR *)&sRecvAddr, sizeof(sRecvAddr));
    if (nResult != 0)
    {
        printf("bind failed:%d
", WSAGetLastError());
        return 1;
    }

    printf("Waiting recv data...
");
    // 阻塞式接收数据
    nResult = recvfrom(s, szBuf, nBufLen, 0, (SOCKADDR *)&sSendAddr, &nSenderAddrSize);
    if (nResult == SOCKET_ERROR)
    {
        printf("recvfrom failed:%d
", WSAGetLastError());
    }
    else{
        printf("SenderIP  :%s
", inet_ntoa(sSendAddr.sin_addr));
        printf("SenderData:%s
", szBuf);
    }
    // 关闭Socket连接
    nResult = closesocket(s);
    if (nResult == SOCKET_ERROR)
    {
        printf("closesocket failed:%d
", WSAGetLastError());
        return 1;
    }
    // 清理Socket
    WSACleanup();

    system("pause");
    return 0;
}

发送端

#include <stdio.h>
#include <WinSock2.h>
#include <Windows.h>

#pragma comment(lib,"WS2_32.lib")

int main(void)
{
    WSADATA wsd;
    SOCKET s;

    if (WSAStartup(MAKEWORD(2, 2), &wsd))
    {
        printf("WSAStartup failed!
");
        return 1;
    }

    s = socket(AF_INET, SOCK_DGRAM, 0);
    if (s == INVALID_SOCKET)
    {
        printf("socket failed,Error Code:%d
", WSAGetLastError());
        WSACleanup();
        return 1;
    }
    SOCKADDR_IN addr;
    SOCKET sockClient = socket(AF_INET, SOCK_DGRAM, 0);

    addr.sin_family = AF_INET;
    addr.sin_addr.S_un.S_addr = inet_addr("172.18.0.67");
    addr.sin_port = htons(1401);

    sendto(sockClient, "测试UDP通信！", 50, 0, (sockaddr *)&addr, 50);
    closesocket(s);
    WSACleanup();
    printf("Hello World!
");
    system("pause");
    return 0;
}

效果图