Re: Socket question... [C# but not only] - C# Discussion Boards

27-Jan-05 17:49

Hi all,
I would like to write a C# Client-Server application, using Socket class (Not NetworkStreams or else)...

My problem is that I want to handle messages with unknown size... my server application uses a fixed-size receiving buffer (1024 bytes)... If I start flooding the server with small messages (let's say 20 bytes), server will store all the messages in the buffer with the same receive call... And I don't know how to recognize every message... I thought an end-tag would be a good idea, but since in the buffer could be every kind of data, I don't know if the tag could be a part of the message... if so, there could be decoding problems (if more than one message in the receiving buffer)... I thought about a start-tag and end-tag... but the problem remains... moreover this would increase too much packet length...

any suggestion? Frown | :(

J4amieC27-Jan-05 22:25

J4amieC

27-Jan-05 22:25

Correct me if im wrong, but isnt the stream of data sent over a Socket of type NetworkStream?

Im not sure you've really provided enough info to give you some accurate answers. How will clients connect to this "server"? Are they not able to indicate to the server <bom>message<eom>? What are you expecting the server to do with the data? Can it not store each message separately? Why not? etc etc

Daniele Mancini28-Jan-05 1:08

28-Jan-05 1:08

> Correct me if im wrong, but isnt the stream of data sent over a Socket of type NetworkStream?
The socket I'm using actually is a Stream/Tcp socket... I meant I don't want to use too much elaborate classes (like NetworkStream)

> How will clients connect to this "server"?
With a TCP connection (Socket type: Stream)

> Are they not able to indicate to the server message [I suppose "length"]?
Sure, they're able to do so, but in this case I should decide how many bytes will store message lenght in the packet... example: if I decided to store lenght in 4 bytes, and I'm using a uint to identify message lenght, the max number I can record is 4,294,967,295... what if I have a 6GB message?

> What are you expecting the server to do with the data?
I'm trying to write a sort of framework... a customizable platform, so I don't want to know what kind of data will be received by server, and I don't want to use a too strict protocol... moreover I'm interested in performances... (that's why I would avoid end and begin tags)

> Can it not store each message separately? Why not?
That's the core of the problem, I can't find a way to receive a single message... when receiving too many messages (flooding) sockets, to optimize throughput, will receive and store in the buffer more than a single message sent... I would like something like this

while(Message is complete)
{
if(Message is complete)
store data;
else
receive another chunk;
}

The problem is how to find if Message is complete... Frown | :(

jzb27-Jan-05 23:55

jzb

27-Jan-05 23:55

using while loop,

string strMsg = "";
try
{
int nSize = 1024;
if (m_socket != null && m_socket.Connected)
{
byte[] btRec = new byte[nSize];
//受信したバイト数
int bytes=0;
//受信したバイト数よりバッファまで受信を繰り返し実行します
do
{
bytes = m_socket.Receive(btRec,0, nSize, SocketFlags.Partial);
//デコードされた表現を含んでいる文字列を返します
strMsg += Encoding.Default.GetString(btRec, 0, bytes);
}
while(bytes != nSize);
}
}
catch
{
}
return strMsg;

Daniele Mancini28-Jan-05 1:16

28-Jan-05 1:16

quote:
do
{
bytes = m_socket.Receive(btRec,0, nSize, SocketFlags.Partial);
strMsg += Encoding.Default.GetString(btRec, 0, bytes);
}
while(bytes != nSize);

bytes variable will store only how many bytes of the buffer have been written with the Receive call, I'm wrong? Some times ago I tested it, but in this way my program tried to store as much data as it could in the buffer... from MSDN:
"If you are using a connection-oriented Socket, the Receive method will read as much data as is available, up to the size of the buffer."

In this way I can't know if I've received one or more messages with a single receive all Sniff | :^)

Member 132576628-Jan-05 16:45

Member 1325766

28-Jan-05 16:45

i am also having problems with socket class.

i am creating a client/server using sockets (tcp Client and TCP listener) but i want to make it work over the internet bypassing a proxy server. is there any possible way that i could make my program run over the internet with this code?

thank you
<
//for my client class
try
{
ByPassProxy();
clientsocket = new TcpClient(serveraddress, serverport);
ns = clientsocket.GetStream();
sr = new StreamReader(ns);
connected = true;
}

public static void ByPassProxy()

{

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://localhost:8080/STUFF//game.exe");
/*

GenerateGetOrPostRequest("http://localhost:8080/STUFF//game.exe",

"GET",

null);
*/

// add the proxy info

HwrAddProxy(request,"proxyaddress:port","username","password","domain");

// or set it up to go through the same proxy for all responses

Uri proxyURI = new Uri("proxy.dlsu.edu.ph:80");

GlobalProxySelection.Select = new WebProxy(proxyURI);

}

public static HttpWebRequest HwrAddProxy(HttpWebRequest httpRequest,

string proxyUri,

string proxyID,

string proxyPwd,

string proxyDomain)

{

if(httpRequest != null)

{

// create the proxy object

WebProxy proxyInfo = new WebProxy();

// add the address of the proxy server to use

proxyInfo.Address = new Uri(proxyUri);

// tell it to bypass the proxy server for local addresses

proxyInfo.BypassProxyOnLocal = true;

// add any credential information to present to the proxy server

proxyInfo.Credentials = new NetworkCredential(proxyID,

proxyPwd,

proxyDomain);

// assign the proxy information to the request

httpRequest.Proxy = proxyInfo;

}

// return the request

return httpRequest;

}

// for my server class

listener = new TcpListener(IpAddr[0],listenport);
Console.WriteLine(IpAddr[0].ToString());
listener.Start();
while (true)
{
try
{
Socket s = listener.AcceptSocket();
clientsocket = s;
clientservice = new Thread(new ThreadStart(ServiceClient));
clientservice.Start();
}
catch(Exception e)
{
Console.WriteLine(e.ToString() );
}

>

HELP pls!!!!

Gregg Holter27-Jan-05 15:31

Gregg Holter

27-Jan-05 15:31

I would like to create a class that could be used to return values. I stored those values in a property so at times I will just retrieve it. My class looks like this:

Class1<br />
{<br />
 private string _name;<br />
<br />
 public Class1(){}<br />
<br />
 public string Name<br />
 { get { return _name; }<br />
   set { _name = value; }<br />
 }<br />
}

My problem now, lies here: I would like to call those property in a way that "name" variable is an array-like? Meaning if i will use this class, I could have code like this:

Class1 c1 = new Class1();<br />
string name1 = c1.Name[0];<br />
string name2 = c1.Name[1];<br />
...<br />
...<br />
...

Could anyone tell me if it's possible to have a property which is array-like? If yes, how is it done? Thank you very much!!! Smile | :)

Yulianto.27-Jan-05 16:08

Yulianto.

27-Jan-05 16:08

clasClass1
{
private string _name; //declare the string in array.

public Class1(){}

public string[] Name
{ get { return _name; }
set { _name = value; }
}
}

Hope this helps, I`m not sure how it`s done. Tell me if it works

<italic>Work hard and a bit of luck is the key to success.

You don`t need to be genius, to be rich.

Robert Rohde27-Jan-05 20:12

Robert Rohde

27-Jan-05 20:12

A slight error in one line. It should look like:

<br />
private string[] _name;<br />

Daniele Mancini28-Jan-05 1:27

28-Jan-05 1:27

Maybe use an ArrayList (from namespace System.Collections) intead of strings...

using System.Collections

Class1
{
private ArrayList _name=new ArrayList();

public Class1(){}

public string Name
{
get { return _name; }
set { _name=value; }
}
}

in this way this code
Class1 myClass=new Class1();
Console.WriteLine(myClass.Name[0].ToString());
will write on screen the first object stored converted to string... In this way you can store different types of data (or objects), since ArrayList class is supposed to store "object" objects :P
Obviusly you need to know what kind of data you are going to retrieve from the ArrayList... ^^

Gregg Holter28-Jan-05 16:50

Gregg Holter

28-Jan-05 16:50

that didn't work, i've tried it... thanks anyway Smile | :)

S. Senthil Kumar28-Jan-05 8:14

S. Senthil Kumar

28-Jan-05 8:14

Why don't you try property indexers. For eg,

<br />
class Class1<br />
{<br />
   StringArrayClass cs;<br />
<br />
   public StringArrayClass Name<br />
   {<br />
      return cs;<br />
   }<br />
   <br />
<br />
   class StringArrayClass<br />
   {<br />
      public string this[int index]<br />
      {<br />
         return array[index];<br />
      }<br />
   }<br />