c++TCP和UDP编写一个简单的可传输文件的Client/Server网络应用程序

在C++中编写一个既能通过TCP又能通过UDP传输文件的简单Client/Server网络应用需要分别处理这两种协议。下面是一个简化的例子，我们将分别展示TCP服务器接收文件和客户端发送文件的部分。

**TCP服务器 (FileReceiver.cpp)**

#include <iostream>
#include <fstream>
#include <boost/asio.hpp>

using boost::asio::ip::tcp;

class FileReceiver {
public:
    void start_server(int port) {
        try {
            auto io_service = boost::asio::io_service();
            server.listen(tcp::endpoint(tcp::v4(), port));

            for (;;) {
                tcp::socket socket(io_service);
                server.accept(socket);

                std::string filename;
                std::getline(socket, filename); // 接收文件名

                std::ifstream file(filename, std::ios::binary);
                if (!file) {
                    std::cerr << "Failed to open file: " << filename << std::endl;
                    continue;
                }

                boost::array<char, 4096> buffer;
                while (std::streamsize read_size = file.read(buffer.data(), sizeof(buffer))) {
                    socket.write(buffer.data(), read_size);
                }
                
                file.close();

                std::cout << "Received file: " << filename << std::endl;
            }
        } catch (std::exception& e) {
            std::cerr << "Error: " << e.what() << std::endl;
        }
    }
};

int main() {
    FileReceiver fr;
    fr.start_server(8080);
    return 0;
}

**TCP客户端 (FileSender.cpp)**

#include <iostream>
#include <fstream>
#include <boost/asio.hpp>

using boost::asio::ip::tcp;

class FileSender {
public:
    void send_file(const std::string& host, int port, const std::string& filename) {
        try {
            auto io_service = boost::asio::io_service();
            tcp::resolver resolver(io_service);
            tcp::resolver::query query(host, std::to_string(port));
            tcp::resolver::iterator endpoint_iterator = resolver.resolve(query);

            tcp::socket socket(io_service);
            boost::asio::connect(socket, endpoint_iterator);

            std::ofstream file(filename, std::ios::binary);
            if (!file) {
                std::cerr << "Failed to open file: " << filename << std::endl;
                return;
            }

            char buffer[4096];
            std::ifstream source_file(filename, std::ios::binary);
            while (source_file.read(buffer, sizeof(buffer))) {
                socket.write(buffer, sizeof(buffer));
            }
            source_file.close();

            std::cout << "Sent file: " << filename << std::endl;
        } catch (std::exception& e) {
            std::cerr << "Error: " << e.what() << std::endl;
        }
    }
};

int main() {
    FileSender fs;
    fs.send_file("localhost", 8080, "test.txt");
    return 0;
}