如何通过c＃中的socket发送文件
我有服务器和客户端控制台应用程序，可以很好地进行通信以及发送一些字符 这是代码……
服务器
public static void Main() { try { IPAddress ipAd = IPAddress.Parse("127.0.0.1"); /* Initializes the Listener */ TcpListener myList = new TcpListener(ipAd, 1234); /* Start Listeneting at the specified port */ myList.Start(); Console.WriteLine("The server is running at port 8001..."); Console.WriteLine("The local End point is :" + myList.LocalEndpoint); Console.WriteLine("Waiting for a connection....."); Socket s = myList.AcceptSocket(); Console.WriteLine("Connection accepted from " + s.RemoteEndPoint); byte[] b = new byte[100]; int k = s.Receive(b); Console.WriteLine("Recieved..."); for (int i = 0; i < k; i++) Console.Write(Convert.ToChar(b[i])); ASCIIEncoding asen = new ASCIIEncoding(); s.Send(asen.GetBytes("The string was recieved by the server.")); Console.WriteLine("\nSent Acknowledgement"); /* clean up */ s.Close(); myList.Stop(); } catch (Exception e) { Console.WriteLine("Error..... " + e.StackTrace); } } 客户
public static void Main() { try { TcpClient tcpclnt = new TcpClient(); Console.WriteLine("Connecting..."); tcpclnt.Connect("127.0.0.1", 1234); Console.WriteLine("Connected"); Console.Write("Enter the string to be transmitted: "); String str = Console.ReadLine(); Stream stm = tcpclnt.GetStream(); ASCIIEncoding asen = new ASCIIEncoding(); byte[] ba = asen.GetBytes(str); Console.WriteLine("Transmitting..."); stm.Write(ba, 0, ba.Length); byte[] bb = new byte[100]; int k = stm.Read(bb, 0, 100); for (int i = 0; i < k; i++) Console.Write(Convert.ToChar(bb[i])); tcpclnt.Close(); } catch (Exception e) { Console.WriteLine("Error... " + e.StackTrace); } }
现在，我需要添加代码算法，该算法将通过相同的应用程序发送文件。 要实现的关键是在客户端中使用Socket.Send。 我不确定该文件的序列化和反序列化。
任何暗示，建议和建议都是值得欢迎的。 谢谢。
根据要求，您可以在客户端执行以下操作 – 正如本文所建议的那样，除了您可能要考虑将同步Send部分更改为异步Send如下所示：
clientSocket.BeginSend(bytes, 0, bytes.Length, SocketFlags.None, endSendCallback, clientSocket); //use async
你的回调可能如下所示：
private static void endSendCallback(IAsyncResult ar) { try { SocketError errorCode; int result = clientSocket.EndSend(ar, out errorCode); Console.WriteLine(errorCode == SocketError.Success ? "Successful! The size of the message sent was :" + result.ToString() : "Error with error code: " + errorCode.ToString() //you probably want to consider to resend if there is error code, but best practice is to handle the error one by one ); } catch (Exception e) { //exception Console.WriteLine("Unhandled EndSend Exception! " + e.ToString()); //do something like retry or just report that the sending fails //But since this is an exception, it probably best NOT to retry } }
至于上述更改后的完整客户端代码如何：
using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Sockets; using System.Text; using System.Threading.Tasks; namespace TcpClientConsoleApplication { class Program { const int PORT_NO = 2201; const string SERVER_IP = "127.0.0.1"; static Socket clientSocket; //put here static void Main(string[] args) { //Similarly, start defining your client socket as soon as you start. clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); loopConnect(3, 3); //for failure handling string result = ""; do { result = Console.ReadLine(); //you need to change this part if (result.ToLower().Trim() != "exit") { byte[] bytes = Encoding.ASCII.GetBytes(result); //Again, note that your data is actually of byte[], not string //do something on bytes by using the reference such that you can type in HEX STRING but sending thing in bytes clientSocket.BeginSend(bytes, 0, bytes.Length, SocketFlags.None, endSendCallback, clientSocket); //use async //clientSocket.Send(bytes); use this for sync send } } while (result.ToLower().Trim() != "exit"); } private static void endSendCallback(IAsyncResult ar) { try { SocketError errorCode; int result = clientSocket.EndSend(ar, out errorCode); Console.WriteLine(errorCode == SocketError.Success ? "Successful! The size of the message sent was :" + result.ToString() : "Error with error code: " + errorCode.ToString() //you probably want to consider to resend if there is error code, but best practice is to handle the error one by one ); } catch (Exception e) { //exception Console.WriteLine("Unhandled EndSend Exception! " + e.ToString()); //do something like retry or just report that the sending fails //But since this is an exception, it probably best NOT to retry } } static void loopConnect(int noOfRetry, int attemptPeriodInSeconds) { int attempts = 0; while (!clientSocket.Connected && attempts < noOfRetry) { try { ++attempts; IAsyncResult result = clientSocket.BeginConnect(IPAddress.Parse(SERVER_IP), PORT_NO, endConnectCallback, null); result.AsyncWaitHandle.WaitOne(TimeSpan.FromSeconds(attemptPeriodInSeconds)); System.Threading.Thread.Sleep(attemptPeriodInSeconds * 1000); } catch (Exception e) { Console.WriteLine("Error: " + e.ToString()); } } if (!clientSocket.Connected) { Console.WriteLine("Connection attempt is unsuccessful!"); return; } } private const int BUFFER_SIZE = 4096; private static byte[] buffer = new byte[BUFFER_SIZE]; //buffer size is limited to BUFFER_SIZE per message private static void endConnectCallback(IAsyncResult ar) { try { clientSocket.EndConnect(ar); if (clientSocket.Connected) { clientSocket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), clientSocket); } else { Console.WriteLine("End of connection attempt, fail to connect..."); } } catch (Exception e) { Console.WriteLine("End-connection attempt is unsuccessful! " + e.ToString()); } } const int MAX_RECEIVE_ATTEMPT = 10; static int receiveAttempt = 0; private static void receiveCallback(IAsyncResult result) { System.Net.Sockets.Socket socket = null; try { socket = (System.Net.Sockets.Socket)result.AsyncState; if (socket.Connected) { int received = socket.EndReceive(result); if (received > 0) { receiveAttempt = 0; byte[] data = new byte[received]; Buffer.BlockCopy(buffer, 0, data, 0, data.Length); //There are several way to do this according to https://stackoverflow.com/questions/5099604/any-faster-way-of-copying-arrays-in-c in general, System.Buffer.memcpyimpl is the fastest //DO ANYTHING THAT YOU WANT WITH data, IT IS THE RECEIVED PACKET! //Notice that your data is not string! It is actually byte[] //For now I will just print it out Console.WriteLine("Server: " + Encoding.UTF8.GetString(data)); socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), socket); } else if (receiveAttempt < MAX_RECEIVE_ATTEMPT) { //not exceeding the max attempt, try again ++receiveAttempt; socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), socket); } else { //completely fails! Console.WriteLine("receiveCallback is failed!"); receiveAttempt = 0; clientSocket.Close(); } } } catch (Exception e) { // this exception will happen when "this" is be disposed... Console.WriteLine("receiveCallback is failed! " + e.ToString()); } } } }
有关上述代码如何工作的完整说明（请注意，第7点已更改，而第8点已添加为异步Send ）：
客户：
-
类似地，将
Socket类放在类上下文而不是方法上下文中，并在启动程序时立即对其进行初始化const int PORT_NO = 2201; const string SERVER_IP = "127.0.0.1"; static Socket clientSocket; //put here static void Main(string[] args) { //Similarly, start defining your client socket as soon as you start. clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); //your other main routines } -
然后开始通过
BeginConnect连接。 我通常会通过LoopConnect进一步处理这样的故障处理。static void loopConnect(int noOfRetry, int attemptPeriodInSeconds) { int attempts = 0; while (!clientSocket.Connected && attempts < noOfRetry) { try { ++attempts; IAsyncResult result = clientSocket.BeginConnect(IPAddress.Parse(SERVER_IP), PORT_NO, endConnect, null); result.AsyncWaitHandle.WaitOne(TimeSpan.FromSeconds(attemptPeriodInSeconds)); System.Threading.Thread.Sleep(attemptPeriodInSeconds * 1000); } catch (Exception e) { Console.WriteLine("Error: " + e.ToString()); } } if (!clientSocket.Connected) { Console.WriteLine("Connection attempt is unsuccessful!"); return; } } -
与您对服务器的操作类似的概念
BeginAccept您需要为您使用的BeginConnect定义endConnectCallback。 但在这里， 与需要重新调用BeginAccept服务器不同 ，一旦连接，您不需要执行任何新的BeginConnect因为您只需要连接一次 。 -
您可能想要声明
buffer等。然后，在连接之后，不要忘记下一个BeginReceive来处理消息检索部分（与服务器类似）private const int BUFFER_SIZE = 4096; private static byte[] buffer = new byte[BUFFER_SIZE]; //buffer size is limited to BUFFER_SIZE per message private static void endConnectCallback(IAsyncResult ar) { try { clientSocket.EndConnect(ar); if (clientSocket.Connected) { clientSocket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), clientSocket); } else { Console.WriteLine("End of connection attempt, fail to connect..."); } } catch (Exception e) { Console.WriteLine("End-connection attempt is unsuccessful! " + e.ToString()); } } -
当然，您需要定义您的
receiveCallback，就像您为服务器所做的那样。 是的，正如您所猜测的那样，它几乎与您为服务器所做的完全相同！ -
您可以使用数据执行任何操作。 请注意，您收到的数据实际上是
byte[]，而不是string。 所以你可以用它做任何事情。 但是，例如 ，我将使用string来显示。const int MAX_RECEIVE_ATTEMPT = 10; static int receiveAttempt = 0; private static void receiveCallback(IAsyncResult result) { System.Net.Sockets.Socket socket = null; try { socket = (System.Net.Sockets.Socket)result.AsyncState; if (socket.Connected) { int received = socket.EndReceive(result); if (received > 0) { receiveAttempt = 0; byte[] data = new byte[received]; Buffer.BlockCopy(buffer, 0, data, 0, data.Length); //copy the data from your buffer //DO ANYTHING THAT YOU WANT WITH data, IT IS THE RECEIVED PACKET! //Notice that your data is not string! It is actually byte[] //For now I will just print it out Console.WriteLine("Server: " + Encoding.UTF8.GetString(data)); socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), socket); } else if (receiveAttempt < MAX_RECEIVE_ATTEMPT) { //not exceeding the max attempt, try again ++receiveAttempt; socket.BeginReceive(buffer, 0, buffer.Length, SocketFlags.None, new AsyncCallback(receiveCallback), socket); } else { //completely fails! Console.WriteLine("receiveCallback is failed!"); receiveAttempt = 0; clientSocket.Close(); } } } catch (Exception e) { // this exception will happen when "this" is be disposed... Console.WriteLine("receiveCallback is failed! " + e.ToString()); } } -
下一个（在最后一个之前） - 是的，再次，正如您已经猜到的那样，您只需要在主程序上执行某些操作 - 假设您要将其用于
BeginSend数据。 因为您使用Console但是希望它以byte[]发送，所以您需要进行转换（请参阅链接post的服务器9中的说明）。static void Main(string[] args) { //Similarly, start defining your client socket as soon as you start. clientSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); loopConnect(3, 3); //for failure handling string result = ""; do { result = Console.ReadLine(); //you need to change this part if (result.ToLower().Trim() != "exit") { byte[] bytes = Encoding.ASCII.GetBytes(result); //Again, note that your data is actually of byte[], not string //do something on bytes by using the reference such that you can type in HEX STRING but sending thing in bytes clientSocket.BeginSend(bytes, 0, bytes.Length, SocketFlags.None, endSendCallback, clientSocket); //use async //clientSocket.Send(bytes); use this for sync send } } while (result.ToLower().Trim() != "exit"); } -
最后，在最后，你只需要声明异步
EndSend回调函数，你就完成了！private static void endSendCallback(IAsyncResult ar) { try { SocketError errorCode; int result = clientSocket.EndSend(ar, out errorCode); Console.WriteLine(errorCode == SocketError.Success ? "Successful! The size of the message sent was :" + result.ToString() : "Error with error code: " + errorCode.ToString() //you probably want to consider to resend if there is error code, but best practice is to handle the error one by one ); } catch (Exception e) { //exception Console.WriteLine("Unhandled EndSend Exception! " + e.ToString()); //do something like retry or just report that the sending fails //But since this is an exception, it probably best NOT to retry } }
File.ReadAllBytes（字符串路径）将为您提供文件的字节数组。
File.WriteAllBytes（string path，byte [] bytes）将把它写入磁盘。
帮助区分文件/命令/状态/等。 您可以在前面添加一个字节标题的消息内容。 枚举：字节可能在这里派上用场。
您只需要将文件作为字节数组读取，然后通过线路发送该字节数组
var bytes = File.ReadAllBytes(path); stm.Write(ba, 0, ba.Length);