Server(UDP).cpp

#include <stdio.h>
#include <winsock2.h>
#include<WS2tcpip.h>
#pragma comment(lib, "ws2_32.lib")

int main(int argc, char* argv[]) {
	WSADATA wsaData;
	WORD sockVersion = MAKEWORD(2, 2);
	if (WSAStartup(sockVersion, &wsaData) != 0) {
		return 0;
	}

	SOCKET serSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
	if (serSocket == INVALID_SOCKET) {
		printf("socket error !");
		return 0;
	}

	sockaddr_in serAddr;
	serAddr.sin_family = AF_INET;
	serAddr.sin_port = htons(8888);
	serAddr.sin_addr.S_un.S_addr = INADDR_ANY;
	if (bind(serSocket, (sockaddr*)&serAddr, sizeof(serAddr)) == SOCKET_ERROR) {
		printf("bind error !");
		closesocket(serSocket);
		return 0;
	}

	sockaddr_in remoteAddr;
	int nAddrLen = sizeof(remoteAddr);
	while (true) {
		printf("等待連線...\n");
		char recvData[255];
		int ret = recvfrom(serSocket, recvData, 255, 0, (sockaddr*)&remoteAddr, &nAddrLen);
		if (ret > 0)
		{
			recvData[ret] = 0x00;
			char sendBuf[20] = { '\0' };
			printf("接受到一個連接：%s \r\n", inet_ntop(AF_INET, (void*)&remoteAddr.sin_addr, sendBuf, 16));
			printf(recvData);
			printf("\n");

		}

		const char* sendData = "一個來自服務端的UDP數據包\n";
		sendto(serSocket, sendData, strlen(sendData), 0, (sockaddr*)&remoteAddr, nAddrLen);

	}
	closesocket(serSocket);
	WSACleanup();
	return 0;
}