Data on udp port

Since i have started to work on class UdpClient, i just wanted to know if i could proceed with that only.
The problem i am facing is while receiving data on udp port, the variable bytesOnSocket is always 0, even when i am sending some data to PC from Hercules.The code is as shown below:
Please Note that Hercules is a tool used, wherein you can see the communications happening on a udp/tcp port when u bind to that port by giving a port number and IP address
 
UdpClient socket = new UdpClient("10.99.8.97", 5555);
 
//This is for sending the data, and it works fine
byte[] data = new byte[] { 0xbb, 0x10, 0x75, 0x12, 0x99, 0xcc, 0xdd };
int datalength = data.Length;
socket.Send(data, datalength);
 
//This is for receiving the data:
byte[] data1 = new byte[1024];
IPAddress ip = IPAddress.Parse("10.99.8.97");
IPEndPoint endpoint = new IPEndPoint(ip, 5555);
int bytesOnSocket = socket.Available;
if (bytesOnSocket != 0)
{
data1 = socket.Receive(ref endpoint);
string strData = Encoding.ASCII.GetString(data1);
}
Please correct me if i am wrong
 

try this: This is udp server side program. If u need any thing more reply me..
 
namespace Server
{
//The commands for interaction between the server and the client
enum Command
{
Login, //Log into the server
Logout, //Logout of the server
Message, //Send a text message to all the chat clients
List, //Get a list of users in the chat room from the server
Null //No command
}
public partial class SGSserverForm : Form
{
//The ClientInfo structure holds the required information about every
//client connected to the server
struct ClientInfo
{
public EndPoint endpoint; //Socket of the client
public string strName; //Name by which the user logged into the chat room
}
//The collection of all clients logged into the room (an array of type ClientInfo)
ArrayList clientList;
//The main socket on which the server listens to the clients
Socket serverSocket;
byte[] byteData = new byte[1024];
public SGSserverForm()
{
clientList = new ArrayList();
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
try
{
CheckForIllegalCrossThreadCalls = false;
//We are using UDP sockets
serverSocket = new Socket(AddressFamily.InterNetwork,
SocketType.Dgram, ProtocolType.Udp);
//Assign the any IP of the machine and listen on port number 1000
IPEndPoint ipEndPoint = new IPEndPoint(IPAddress.Any, 1000);
//Bind this address to the server
serverSocket.Bind(ipEndPoint);

IPEndPoint ipeSender = new IPEndPoint(IPAddress.Any, 0);
//The epSender identifies the incoming clients
EndPoint epSender = (EndPoint) ipeSender;
//Start receiving data
serverSocket.BeginReceiveFrom (byteData, 0, byteData.Length,
SocketFlags.None, ref epSender, new AsyncCallback(OnReceive), epSender);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "SGSServerUDP",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
private void OnReceive(IAsyncResult ar)
{
try
{
IPEndPoint ipeSender = new IPEndPoint(IPAddress.Any, 0);
EndPoint epSender = (EndPoint)ipeSender;
serverSocket.EndReceiveFrom (ar, ref epSender);

//Transform the array of bytes received from the user into an
//intelligent form of object Data
Data msgReceived = new Data(byteData);
//We will send this object in response the users request
Data msgToSend = new Data();
byte [] message;

//If the message is to login, logout, or simple text message
//then when send to others the type of the message remains the same
msgToSend.cmdCommand = msgReceived.cmdCommand;
msgToSend.strName = msgReceived.strName;
switch (msgReceived.cmdCommand)
{
case Command.Login:

//When a user logs in to the server then we add her to our
//list of clients
ClientInfo clientInfo = new ClientInfo();
clientInfo.endpoint = epSender;
clientInfo.strName = msgReceived.strName;
clientList.Add(clientInfo);

//Set the text of the message that we will broadcast to all users
msgToSend.strMessage = "<<<" + msgReceived.strName + " has joined the room>>>";
break;
case Command.Logout:

//When a user wants to log out of the server then we search for her
//in the list of clients and close the corresponding connection
int nIndex = 0;
foreach (ClientInfo client in clientList)
{
if (client.endpoint == epSender)
{
clientList.RemoveAt(nIndex);
break;
}
++nIndex;
}

msgToSend.strMessage = "<<<" + msgReceived.strName + " has left the room>>>";
break;
case Command.Message:
//Set the text of the message that we will broadcast to all users
msgToSend.strMessage = msgReceived.strName + ": " + msgReceived.strMessage;
break;
case Command.List:
//Send the names of all users in the chat room to the new user
msgToSend.cmdCommand = Command.List;
msgToSend.strName = null;
msgToSend.strMessage = null;
//Collect the names of the user in the chat room
foreach (ClientInfo client in clientList)
{
//To keep things simple we use asterisk as the marker to separate the user names
msgToSend.strMessage += client.strName + "*";
}
message = msgToSend.ToByte();
//Send the name of the users in the chat room
serverSocket.BeginSendTo (message, 0, message.Length, SocketFlags.None, epSender,
new AsyncCallback(OnSend), epSender);
break;
}
if (msgToSend.cmdCommand != Command.List) //List messages are not broadcasted
{
message = msgToSend.ToByte();
foreach (ClientInfo clientInfo in clientList)
{
if (clientInfo.endpoint != epSender ||
msgToSend.cmdCommand != Command.Login)
{
//Send the message to all users
serverSocket.BeginSendTo (message, 0, message.Length, SocketFlags.None, clientInfo.endpoint,
new AsyncCallback(OnSend), clientInfo.endpoint);
}
}
txtLog.Text += msgToSend.strMessage + "\r\n";
}
//If the user is logging out then we need not listen from her
if (msgReceived.cmdCommand != Command.Logout)
{
//Start listening to the message send by the user
serverSocket.BeginReceiveFrom (byteData, 0, byteData.Length, SocketFlags.None, ref epSender,
new AsyncCallback(OnReceive), epSender);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "SGSServerUDP", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
public void OnSend(IAsyncResult ar)
{
try
{
serverSocket.EndSend(ar);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "SGSServerUDP", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
//The data structure by which the server and the client interact with
//each other
class Data
{
//Default constructor
public Data()
{
this.cmdCommand = Command.Null;
this.strMessage = null;
this.strName = null;
}
//Converts the bytes into an object of type Data
public Data(byte[] data)
{
//The first four bytes are for the Command
this.cmdCommand = (Command)BitConverter.ToInt32(data, 0);
//The next four store the length of the name
int nameLen = BitConverter.ToInt32(data, 4);
//The next four store the length of the message
int msgLen = BitConverter.ToInt32(data, 8);
//This check makes sure that strName has been passed in the array of bytes
if (nameLen > 0)
this.strName = Encoding.UTF8.GetString(data, 12, nameLen);
else
this.strName = null;
//This checks for a null message field
if (msgLen > 0)
this.strMessage = Encoding.UTF8.GetString(data, 12 + nameLen, msgLen);
else
this.strMessage = null;
}
//Converts the Data structure into an array of bytes
public byte[] ToByte()
{
List<byte> result = new List<byte>();
//First four are for the Command
result.AddRange(BitConverter.GetBytes((int)cmdCommand));
//Add the length of the name
if (strName != null)
result.AddRange(BitConverter.GetBytes(strName.Length));
else
result.AddRange(BitConverter.GetBytes(0));
//Length of the message
if (strMessage != null)
result.AddRange(BitConverter.GetBytes(strMessage.Length));
else
result.AddRange(BitConverter.GetBytes(0));
//Add the name
if (strName != null)
result.AddRange(Encoding.UTF8.GetBytes(strName));
//And, lastly we add the message text to our array of bytes
if (strMessage != null)
result.AddRange(Encoding.UTF8.GetBytes(strMessage));
return result.ToArray();
}
public string strName; //Name by which the client logs into the room
public string strMessage; //Message text
public Command cmdCommand; //Command type (login, logout, send message, etcetera)
}
}