C# Socket 大文件传输代码

以下是 C# 中使用 Socket 进行大文件传输的示例代码：

服务器端代码：

using System;
using System.IO;
using System.Net;
using System.Net.Sockets;

class Program {
    static void Main(string[] args) {
        // 设置监听地址和端口号
        IPEndPoint endPoint = new IPEndPoint(IPAddress.Any, 8888);
        Socket listenSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

        // 开始监听
        listenSocket.Bind(endPoint);
        listenSocket.Listen(10);

        Console.WriteLine("等待客户端连接...");

        // 接收客户端连接请求
        Socket clientSocket = listenSocket.Accept();

        // 接收文件名
        byte[] fileNameBytes = new byte[1024];
        int recvLength = clientSocket.Receive(fileNameBytes);
        string fileName = Encoding.UTF8.GetString(fileNameBytes, 0, recvLength);

        Console.WriteLine("接收到文件名：" + fileName);

        // 接收文件大小
        byte[] fileSizeBytes = new byte[8];
        recvLength = clientSocket.Receive(fileSizeBytes);
        long fileSize = BitConverter.ToInt64(fileSizeBytes, 0);

        Console.WriteLine("接收到文件大小：" + fileSize);

        // 创建文件流并保存文件
        using (FileStream fileStream = new FileStream(fileName, FileMode.Create)) {
            byte[] buffer = new byte[1024];
            long totalRecvLength = 0;
            int recvCount;

            while (totalRecvLength < fileSize) {
                recvCount = clientSocket.Receive(buffer);
                fileStream.Write(buffer, 0, recvCount);
                totalRecvLength += recvCount;
            }
        }

        Console.WriteLine("文件接收完成！");

        // 终止连接
        clientSocket.Shutdown(SocketShutdown.Both);
        clientSocket.Close();
        listenSocket.Close();
    }
}

客户端代码：

using System;
using System.IO;
using System.Net;
using System.Net.Sockets;

class Program {
    static void Main(string[] args) {
        // 连接服务器
        IPAddress serverIP = IPAddress.Parse("127.0.0.1");
        IPEndPoint endPoint = new IPEndPoint(serverIP, 8888);
        Socket clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
        clientSocket.Connect(endPoint);

        Console.WriteLine("连接服务器成功！");

        // 发送文件名
        string fileName = "test.txt";
        byte[] fileNameBytes = Encoding.UTF8.GetBytes(fileName);
        clientSocket.Send(fileNameBytes);

        Console.WriteLine("发送文件名：" + fileName);

        // 发送文件大小
        FileInfo fileInfo = new FileInfo(fileName);
        long fileSize = fileInfo.Length;
        byte[] fileSizeBytes = BitConverter.GetBytes(fileSize);
        clientSocket.Send(fileSizeBytes);

        Console.WriteLine("发送文件大小：" + fileSize);

        // 发送文件内容
        using (FileStream fileStream = new FileStream(fileName, FileMode.Open)) {
            byte[] buffer = new byte[1024 * 1024];
            int sendCount;

            while ((sendCount = fileStream.Read(buffer, 0, buffer.Length)) > 0) {
                clientSocket.Send(buffer, sendCount, SocketFlags.None);
            }
        }

        Console.WriteLine("文件发送完成！");

        // 终止连接
        clientSocket.Shutdown(SocketShutdown.Both);
        clientSocket.Close();
    }
}

注：以上代码只是一个简单的示例，实际应用中还需要进行异常处理、数据校验等操作。为了避免内存溢出，客户端和服务器端需要分段读取和发送文件内容。在示例代码中，客户端和服务器端每次读取和发送 1MB 的数据。如果需要传输的文件非常大，建议使用分块传输和多线程传输等优化方式。