在C++中实现UDP发送和接收可以使用socket编程。下面是一个简单的示例代码：
发送UDP数据包：
#include <iostream>#include <string>#include <cstring>#include <unistd.h>#include <sys/socket.h>#include <netinet/in.h>int main() { int sockfd; struct sockaddr_in serverAddr; // 创建UDP socket sockfd = socket(AF_INET, SOCK_DGRAM, 0); if (sockfd < 0) { std::cerr << "Failed to create socket" << std::endl; return -1; } // 设置服务器地址和端口 serverAddr.sin_family = AF_INET; serverAddr.sin_port = htons(12345); serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1"); // 发送数据 std::string message = "Hello, UDP!"; sendto(sockfd, message.c_str(), message.length(), 0, (struct sockaddr*)&serverAddr, sizeof(serverAddr)); close(sockfd); return 0;}接收UDP数据包：
#include <iostream>#include <string>#include <cstring>#include <unistd.h>#include <sys/socket.h>#include <netinet/in.h>int main() { int sockfd; struct sockaddr_in serverAddr, clientAddr; socklen_t addrLen = sizeof(clientAddr); char buffer[1024]; // 创建UDP socket sockfd = socket(AF_INET, SOCK_DGRAM, 0); if (sockfd < 0) { std::cerr << "Failed to create socket" << std::endl; return -1; } // 设置服务器地址和端口 serverAddr.sin_family = AF_INET; serverAddr.sin_port = htons(12345); serverAddr.sin_addr.s_addr = INADDR_ANY; // 绑定地址和端口 bind(sockfd, (struct sockaddr*)&serverAddr, sizeof(serverAddr)); // 接收数据 int bytesReceived = recvfrom(sockfd, buffer, 1024, 0, (struct sockaddr*)&clientAddr, &addrLen); buffer[bytesReceived] = '\0'; std::cout << "Received: " << buffer << std::endl; close(sockfd); return 0;}以上代码实现了一个简单的UDP发送和接收示例，可以根据实际需求进行进一步的扩展和优化。
