我想将数据从 android 发送到 C#。C# 是服务器。Android 是客户端我将我的计算机连接到移动热点，但我收到此错误：
无法连接到 192.168.1.15（端口 4444）：连接失败：ENETUNREACH（网络无法访问
这是java代码：
public class MainActivity extends Activity {
//TextView tv=(TextView) findViewById(R.id.textView2);
EditText edittext1;
private TCPClient mTcpClient;
private Button btnIP;
private TextView txt1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
txt1 = (TextView) findViewById(R.id.textView1);
final EditText editText = (EditText)findViewById(R.id.edit_message);
edittext1=(EditText) findViewById(R.id.editText1);
btnIP=(Button) findViewById(R.id.button1);
Button bt2=(Button) findViewById(R.id.button2);
bt2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
txt1.setText(TCPClient.log) ;
}
});
Button send = (Button)findViewById(R.id.send_button);
// connect to the server
new connectTask().execute("");
btnIP.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
TCPClient.SERVERIP=edittext1.getText().toString();
new connectTask().execute("");
}
});
send.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View view) {
String message = editText.getText().toString();
//sends the message to the server
if (mTcpClient != null)
{
mTcpClient.sendMessage(message);
}
editText.setText("");
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public class connectTask extends AsyncTask<String,String,TCPClient>
{
@Override
protected TCPClient doInBackground(String... message)
{
mTcpClient = new TCPClient(new OnMessageReceived()
{
@Override public void messageReceived(String message)
{
publishProgress(message);
}
});
Looper.prepare();
mTcpClient.run();
return null;
}
@Override
protected void onProgressUpdate(String... values)
{
super.onProgressUpdate(values);
}
}
public static class TCPClient
{
private String serverMessage;
public static String SERVERIP = "192.168.1.15";
public static final int SERVERPORT = 4444;
private OnMessageReceived mMessageListener = null;
public static String log="";
private boolean mRun = false;
PrintWriter out;
BufferedReader in;
DataOutputStream dataOutputStream = null;
//OutputStream os;
public TCPClient(OnMessageReceived listener)
{
mMessageListener = listener;
}
public void sendMessage(String message)
{
if (out != null && !out.checkError())
{
/* String toSend = "a"; byte[] toSendBytes = toSend.getBytes();
int toSendLen = toSendBytes.length; byte[] toSendLenBytes = new byte[4];
toSendLenBytes[0] = (byte)(toSendLen & 0xff); toSendLenBytes[1] = (byte)((toSendLen >> 8) & 0xff); toSendLenBytes[2] = (byte)((toSendLen >> 16) & 0xff); toSendLenBytes[3] = (byte)((toSendLen >> 24) & 0xff); try { os.write(toSendLenBytes); } catch (IOException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } try { os.write(toSendBytes);
} catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } */
out.print(message);
out.flush();
}
}
public void stopClient()
{
mRun = false;
}
public void run()
{
// TextView tv=(TextView) findViewById(R.id.textView2);
//tv.setText(tv.getText()+"\n"+ "run");
mRun = true;
try
{
InetAddress serverAddr = InetAddress.getByName(SERVERIP);
Log.e("TCP Client", "C: Connecting...");
log="C: Connecting...";
//Toast.makeText(MainActivity.this, "Connecting", Toast.LENGTH_SHORT).show();
//tv.setText(tv.getText()+"\n"+ "Connecting");
//tv.setText(tv.getText()+"\n"+ "Connecting...");
Socket socket = new Socket(serverAddr, SERVERPORT);
/// //os = socket.getOutputStream();
if(socket.isBound())
{
Log.i("SOCKET", "Socket: Connected");
log="Connected";
//tv.setText(tv.getText()+"\n"+ "Connected");
//Toast.makeText(MainActivity.this, "Connected", Toast.LENGTH_SHORT).show();
//tv.setText(tv.getText()+"\n"+ "Connected");
}
else{
Log.e("SOCKET", "Socket: Not Connected");
log="Not Connected";
// tv.setText(tv.getText()+"\n"+ "not Connected");
//Toast.makeText(MainActivity.this, "not Connected", Toast.LENGTH_SHORT).show();
//tv.setText(tv.getText()+"\n"+ " Not Connected");
} try {
out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())), true);
//out.println(new char[]{'h','e'});
//out.flush();
/* dataOutputStream = new DataOutputStream(socket.getOutputStream()); byte[] bytes = new byte[] {1};
* dataOutputStream.write(bytes, 0, bytes.length); */
Log.e("TCP Client", "C: Sent.");
log=" Sent";
Log.e("TCP Client", "C: Done.");
log=" Done";
if(out.checkError())
{
Log.e("PrintWriter", "CheckError");
}
in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
while (mRun)
{
serverMessage = in.readLine();
if (serverMessage != null && mMessageListener != null)
{
mMessageListener.messageReceived(serverMessage);
}
serverMessage = null;
}
Log.e("RESPONSE FROM SERVER", "S: Received Message: '" + serverMessage + "'");
} catch (Exception e) { Log.e("TCP", "S: Error", e); }
finally { socket.close(); }
}
catch (Exception e) { Log.e("TCP", "C: Error", e);
log=e.getMessage();
//tv.setText(tv.getText()+"\n"+ e.getMessage());
}
}
}
}
C#代码：
class Program
{
static private IPAddress getLocalIPAddress()
{
IPHostEntry host;
//string localIP = "";
host = Dns.GetHostEntry(Dns.GetHostName());
foreach (IPAddress ip in host.AddressList)
{
if (ip.AddressFamily == AddressFamily.InterNetwork)
{
// localIP = ip.ToString();
return ip;
//break;
}
}
// return localIP;
return null;
}
static void Main(string[] args)
{
int recv;
byte[] data = new byte[2048];
IPEndPoint ipep = new IPEndPoint(getLocalIPAddress(), 4444);
Socket newsock = new Socket(AddressFamily.InterNetwork, SocketType.Stream,
ProtocolType.Tcp);
newsock.Bind(ipep);
newsock.Listen(10);
Console.WriteLine("Waiting for a client...");
Socket client = newsock.Accept();
IPEndPoint clientep = (IPEndPoint)client.RemoteEndPoint;
Console.WriteLine("Connected with {0} at port{1}", clientep.Address, clientep.Port);
string welcome = "Welcome to my test server";
data = Encoding.ASCII.GetBytes(welcome);
client.Send(data, data.Length, SocketFlags.None);
while (true)
{
data = new byte[1024];
recv = client.Receive(data);
if (recv == 0)
break;
Console.WriteLine(Encoding.ASCII.GetString(data, 0,
recv));
client.Send(data, recv, SocketFlags.None);
}
Console.WriteLine("Disconnected from{0}", clientep.Address);
client.Close();
newsock.Close();
}
}