我正在开发两个应用程序，一个是服务器应用程序，另一个是用于手持设备 应用程序都使用无线连接进行通信。客户端是手持设备，服务器是 运行服务器应用程序的计算机。当我从客户端发送文件到服务器时，它发送 完美没有任何错误，但当客户端请求文件服务器产生错误 就像是 “无法建立连接，因为目标机器主动拒绝它192.168.1.5:9050”
服务器端代码：
private bool SendData(string StrIP)
{
try
{
string strmyFile = Directory.GetCurrentDirectory() + "\\" + "XML" + @"\Login.xml";
char[] delimiter = splitter.ToCharArray();
split = strmyFile.Split(delimiter);
int limit = split.Length;
fName = split[limit - 1].ToString();
byte[] fileName = Encoding.UTF8.GetBytes(fName); //file name
byte[] fileData = File.ReadAllBytes(strmyFile); //file
using (FileStream stream = File.OpenRead(strmyFile))
{
fileData = new byte[stream.Length];
stream.Read(fileData, 0, fileData.Length);
}
byte[] fileNameLen = BitConverter.GetBytes(fileName.Length); //lenght of file name
clientData = new byte[4 + fileName.Length + fileData.Length];
fileNameLen.CopyTo(clientData, 0);
fileName.CopyTo(clientData, 4);
fileData.CopyTo(clientData, 4 + fileName.Length);
System.Net.IPAddress ipAdd = System.Net.IPAddress.Parse(StrIP);
try
{
Socket clientSock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint ipEnd = new IPEndPoint(ipAdd, 9050);
clientSock.Connect(ipEnd); //target machine's ip address and the port number
clientSock.Send(clientData);
clientSock.Close();
ind = 1;
//Socket Sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
//IPEndPoint ipEnd = new IPEndPoint(ipAdd, 9050);
//Sock.Bind(ipEnd);//target machine's ip address and the port number
//Sock.Listen(100);
//Socket clientSock = Sock.Accept();
//clientSock.Send(clientData);
//clientSock.Close();
//ind = 1;
}
catch (Exception ex)
{
req = false;
return false;
}
req = true;
}
catch (Exception ex)
{
}
return true;
}
public class StateObject
{
// Client socket.
public Socket workSocket = null;
public const int BufferSize = 1024 * 5000;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
}
public static ManualResetEvent allDone = new ManualResetEvent(false);
public void StartListening()
{
byte[] bytes = new Byte[1024 * 5000];
IPEndPoint ipEnd = new IPEndPoint(IPAddress.Any, 9050);
Socket listener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
try
{
listener.Bind(ipEnd);
listener.Listen(100);
while (true)
{
allDone.Reset();
// string ip = listener.RemoteEndPoint.ToString();
listener.BeginAccept(new AsyncCallback(AcceptCallback), listener);
allDone.WaitOne();
}
}
catch (Exception ex)
{
}
}
public void AcceptCallback(IAsyncResult ar)
{
allDone.Set();
Socket listener = (Socket)ar.AsyncState;
Socket handler = listener.EndAccept(ar);
StateObject state = new StateObject();
state.workSocket = handler;
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
flag = 0;
}
private bool req = false;
public void ReadCallback(IAsyncResult ar)
{
try
{
int fileNameLen = 1;
String content = String.Empty;
StateObject state = (StateObject)ar.AsyncState;
Socket handler = state.workSocket;
string[] str = new string[2];
str = handler.RemoteEndPoint.ToString().Split(':');
string path = Directory.GetCurrentDirectory() + "\\TEST\\" + str[0].ToString();
if (!Directory.Exists(path))
{
Directory.CreateDirectory(path);
}
if (req == false)
{
Sender snddata = new Sender();
snddata.sendme(str[0].ToString());
SendData(str[0].ToString());
}
int bytesRead = handler.EndReceive(ar);
if (bytesRead > 0)
{
if (flag == 0)
{
fileNameLen = BitConverter.ToInt32(state.buffer, 0);
string fileName = Encoding.UTF8.GetString(state.buffer, 4, fileNameLen);
receivedPath = Directory.GetCurrentDirectory() + "\\TEST\\" + str[0].ToString() + @"\" + fileName;
flag++;
}
if (flag >= 1)
{
BinaryWriter writer = new BinaryWriter(File.Open(receivedPath, FileMode.Append));
if (flag == 1)
{
writer.Write(state.buffer, 4 + fileNameLen, bytesRead - (4 + fileNameLen));
flag++;
}
else
writer.Write(state.buffer, 0, bytesRead);
writer.Close();
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
}
else
{
Invoke(new MyDelegate(LabelWriter));
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
public class Sender
{
public void sendme(string strIP)
{
try
{
// MessageBox.Show("That program can transfer small file. I've test up to 850kb file");
IPEndPoint ipEnd = new IPEndPoint(IPAddress.Any, 9050);
Socket sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
sock.Bind(ipEnd);
sock.Listen(100);
while (true)
{
//clientSock is the socket object of client, so we can use it now to transfer data to client
Socket clientSock = sock.Accept();
string fileName = "Login.xml";// "Your File Name";
string filePath = Directory.GetCurrentDirectory() + "\\" + "XML" + @"\" ;//Your File Path;
byte[] fileNameByte = Encoding.ASCII.GetBytes(fileName);
byte[] fileData = File.ReadAllBytes(filePath + fileName);
byte[] clientData = new byte[4 + fileNameByte.Length + fileData.Length];
byte[] fileNameLen = BitConverter.GetBytes(fileNameByte.Length);
fileNameLen.CopyTo(clientData, 0);
fileNameByte.CopyTo(clientData, 4);
fileData.CopyTo(clientData, 4 + fileNameByte.Length);
clientSock.Send(clientData);
//MessageBox.Show("File:{0} has been sent." + fileName);
}
//sock.Shutdown(SocketShutdown.Both);
//sock.Close();
// Console.ReadLine();
//sendme();
}
catch (Exception ex)
{
MessageBox.Show("File Receiving fail." + ex.Message);
}
}
}
客户端代码：
public class StateObject
{
// Client socket.
public Socket workSocket = null;
public const int BufferSize = 1024;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
}
public static ManualResetEvent allDone = new ManualResetEvent(false);
public void StartListening()
{
byte[] bytes = new Byte[1024];
IPAddress address = IPAddress.Parse(ServerIP);
IPEndPoint ipEnd = new IPEndPoint(address, 9050);
Socket listener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
try
{
listener.Bind(ipEnd);
listener.Listen(100);
while (true)
{
allDone.Reset();
// string ip = listener.RemoteEndPoint.ToString();
listener.BeginAccept(new AsyncCallback(AcceptCallback), listener);
allDone.WaitOne();
}
}
catch (Exception ex)
{
throw ex;
}
}
public void AcceptCallback(IAsyncResult ar)
{
allDone.Set();
Socket listener = (Socket)ar.AsyncState;
Socket handler = listener.EndAccept(ar);
StateObject state = new StateObject();
state.workSocket = handler;
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
flag = 0;
}
public void ReadCallback(IAsyncResult ar)
{
try
{
int fileNameLen = 1;
String content = String.Empty;
StateObject state = (StateObject)ar.AsyncState;
Socket handler = state.workSocket;
//string[] str = new string[2];
//str = handler.RemoteEndPoint.ToString().Split(':');
string path = mypath + "@Login.XML";
if (!Directory.Exists(path))
{
Directory.CreateDirectory(path);
}
int bytesRead = handler.EndReceive(ar);
if (bytesRead > 0)
{
if (flag == 0)
{
fileNameLen = BitConverter.ToInt32(state.buffer, 0);
string fileName = Encoding.UTF8.GetString(state.buffer, 4, fileNameLen);
receivedPath = mypath + "@Login.XML";
flag++;
}
if (flag >= 1)
{
BinaryWriter writer = new BinaryWriter(File.Open(receivedPath, FileMode.Append));
if (flag == 1)
{
writer.Write(state.buffer, 4 + fileNameLen, bytesRead - (4 + fileNameLen));
flag++;
}
else
writer.Write(state.buffer, 0, bytesRead);
writer.Close();
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
}
else
{
Invoke(new MyDelegate(LabelWriter));
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
public void LabelWriter()
{
MessageBox.Show("Data has been received");
Programs p = new Programs();
p.GetFile(serverIP);
}
此代码用于从服务器获取文件。
private void GetLoginTemp()
{
Socket clientSock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
try
{
char[] delimiter = splitter.ToCharArray();
byte[] fileName = Encoding.UTF8.GetBytes("empty"); //file name
byte[] fileData;
fileData = Encoding.UTF8.GetBytes("empty");
//byte[] fileData = reads.ReadToEnd().to; //file
byte[] fileNameLen = BitConverter.GetBytes(fileName.Length); //lenght of file name
clientData = new byte[4 + fileName.Length + fileData.Length];
fileNameLen.CopyTo(clientData, 0);
fileName.CopyTo(clientData, 4);
fileData.CopyTo(clientData, 4 + fileName.Length);
System.Net.IPAddress ipAdd = System.Net.IPAddress.Parse(serverIP);
IPEndPoint ipEnd = new IPEndPoint(ipAdd, 9050);
clientSock.Connect(ipEnd); //target machine's ip address and the port number
clientSock.Send(clientData);
byte[] clientData1 = new byte[1024 * 5000];
string receivedPath = mypath + @"\XML" + @"\Login.xml";
int receivedBytesLen = clientSock.Receive(clientData1);
int fileNameLen1 = BitConverter.ToInt32(clientData1, 0);
string fileName1 = Encoding.ASCII.GetString(clientData1, 4, fileNameLen1);
BinaryWriter bWrite = new BinaryWriter(File.Open(receivedPath + fileName, FileMode.Append)); ;
bWrite.Write(clientData, 4 + fileNameLen1, receivedBytesLen - 4 - fileNameLen1);
//clientSock.Shutdown(SocketShutdown.Send);
clientSock.Close();
}
catch (Exception ex)
{
clientSock.Close();
MessageBox.Show(ex.Message);
}
}
答案 0 :(得分：8)
您似乎认为在文件传输方向上需要第二个TCP连接。这不是必需的，因为TCP连接是全双工流。此外，从服务器返回到客户端也不是一个好的设计，这可能是NAT-ing网关/防火墙的背后。这是FTP的问题（见active vs passive ftp）。
使用客户端已建立的相同连接。您需要在基础TCP之上使用某种协议，让对方知道何时需要数据以及预期的数量。这已经在这里讨论了很多次，例如参见this SO question。
答案 1 :(得分：0)
仅从您收到的错误（我多次出现相同的错误）检查您用于通信的基础流是否未关闭，或者您是否尝试重新使用已关闭的流
您是否有发生错误的特定行？
答案 2 :(得分：0)
您可能需要检查系统防火墙以确保允许连接。使用ping和telnet非常适合调试。
答案 3 :(得分：0)
如果它不是防火墙，我认为让服务器监听（启动服务器）就这么简单
我建议这段代码可以解决您的问题：
var prg = StateObject();
prg.StartListening;
在您管理完之后，请告诉我是否已发送超过8KB的文件