TCP Listener Asnchronous not close client successfully object dispose exception

Question

3.00/5 (2 votes)

See more:

Please verify my code. I am working on tcp listener asynchronously. When i disconnect from all of my clients it gives the following error:
"Cannot access a disposed object.
Object name: System.Net.Sockets.Socket."

C#

 public static void StopServer()
        {
            try
            {
                Status = false;
                listenerSocket.Stop();
                backgroundworkerListener.CancelAsync();
                backgroundworkerListener.Dispose();

                if (ClientDevices != null)
                {
                    foreach (ClientManager mngr in ClientDevices)
                    {
                        mngr.Disconnect();
                    }
                    ClientDevices.Clear();
                }
                GC.Collect();
            }
            catch (ObjectDisposedException ode)
            {
                Console.WriteLine(ode.Message);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }


public bool Disconnect()
       {
           if (this.tcpClient != null )
           {
               try
               {
                   SocketAsyncEventArgs e = new SocketAsyncEventArgs();
                   this.networkStream.Flush();
                   this.networkStream.Close();
                   this.networkStream.Dispose();
                   this.tcpClient.Close();
                   this.tcpClient.Client.Close();
                  // this.tcpClient.Client.DisconnectAsync(e);
                   tcpClient.Client.Shutdown(SocketShutdown.Both);
                   GC.Collect();
                   return true;
               }
               catch (ObjectDisposedException oex)
               {
                   throw new ObjectDisposedException(base.GetType().FullName);
                 //  return false;
               }
               catch
               {
                   return false;
               }
           }
           else
               return true;
       }

Posted 30-Jun-14 2:44am

Muhammad Amman

Updated 30-Jun-14 22:31pm

Rahul VB

v3

Add a Solution

Comments

gggustafson 30-Jun-14 10:54am

Why are you disconnecting clients from the server side? The usual model is to have the client disconnect from the server. I don't see the code where you set up your listener to handle multiple clients. You may need to consider a synchronous solution.

Muhammad Amman 1-Jul-14 3:23am

Actually i created server app for 1000 of clients when i want to close my server application so that it will close and shutdown all clients that are connected it gives error on this line.

tcpClient.Client.Shutdown(SocketShutdown.Both);

It raises that exception:
Cannot access a disposed object.
Object name: System.Net.Sockets.Socket.

I want to shutdown it properly please help rahul thanks

Rahul VB 1-Jul-14 2:47am

Ok, first of all tell me one thing : why have you used :
"this.networkStream.Dispose();". What i mean to say is that when you dispose an object then you cant access it again because the object becomes null.

also on which line does it throw an exception? To find that out firstly remove the try catch block and then tell me. You are bypassing the bug by using try-catch, so dont do that. Let the code break into the debugger and tell me exactly.

There are many things i need to point out:
1) You must know that system.exception is the base class of all the exceptions so if you want to catch an exception and you use a generalized exception handler, that will serve the purpose. But if you want to dig deep inside then you need to use specify the exception in try catch block so as to catch that exception.

So firstly remove the try catch block and tell me that as to where are you getting the exception.

Thanks and Regards,
Rahul

Muhammad Amman 1-Jul-14 3:23am

Actually i created server app for 1000 of clients when i want to close my server application so that it will close and shutdown all clients that are connected it gives error on this line.

tcpClient.Client.Shutdown(SocketShutdown.Both);

It raises that exception:
Cannot access a disposed object.
Object name: System.Net.Sockets.Socket.

I want to shutdown it properly please help rahul thanks

Rahul VB 1-Jul-14 4:18am

Ok, now do one thing just comment the line "this.tcpClient.Close()" and if you still get an error then comment the next line also which is : ""this.tcpClient.Client.Close();

Why am i saying this? It is because when you say Close() then the instance of that object is disposed. So you wont be able to access the object.

So now you need to try out what i said and then you need to run the code again.

Please do let me know, If it does not work, then we will try out something else.

Thanks a Ton,
Rahul

Muhammad Amman 1-Jul-14 5:23am

ThankYou for your response i tried this but i raised same error actually it create a problem on this line

tcpClient.Client.Shutdown(SocketShutdown.Both);
When it read client shutdown then this exception raised :
Cannot access a disposed object.
Object name: System.Net.Sockets.Socket.

One more thing i am using TCP Listener working as asynchronously so multiple clients are connected. I want to shutdown properly my server application at once so that all clients closed. but i am not understanding why shutdown method raises object dispose exception.

Rahul VB 1-Jul-14 5:26am

Ok, i understand that now i will share one link with you just read that link and then you must get some idea. Look at link below:

http://msdn.microsoft.com/en-us/library/system.net.sockets.tcpclient.close%28v=vs.110%29.aspx

gggustafson 1-Jul-14 10:46am

I think that you have provided documentation for the "standard" model of client/server. OP wants to have the server close the connection.

Rahul VB 2-Jul-14 1:08am

Hello Sir,
I understand. I just wanted to make him read that documentation because i thought he would get some clue from it. Because he called "shutdown" after closing the network stream and we cant access a disposed object. This is precisely what that documentation says. That's why in the end he then interchanged the 2 statements.

I hope i was right. Please do correct me if i am wrong.

Thanks a ton,
Rahul

gggustafson 2-Jul-14 10:55am

Absolutely nothing wrong with your reply.

And thank you for sharing your thoughts for the solution to this question. Please keep it up.

Rahul VB 2-Jul-14 14:42pm

Hello Sir,

Thanks a ton, Rahul

2 solutions

Solution 3

Use this one

C#

public bool Disconnect()
       {
           if (this.tcpClient != null )
           {
               try
               {
                   SocketAsyncEventArgs e = new SocketAsyncEventArgs();
                   this.networkStream.Flush();
                   this.networkStream.Close();
                   this.networkStream.Dispose(); 
                   //this.tcpClient.Client.DisconnectAsync(e);
                   tcpClient.Client.Shutdown(SocketShutdown.Both);
                   this.tcpClient.Client.Close();
                   this.tcpClient.Close();
                   GC.Collect();
                   return true;
               }
               catch (ObjectDisposedException oex)
               {
                   throw new ObjectDisposedException(base.GetType().FullName);
                 //  return false;
               }
               catch
               {
                   return false;
               }
           }
           else
               return true;
       }

Posted 1-Jul-14 0:00am

CB Sharma

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Muhammad Amman · Accepted Answer · 2014-06-30T23:51:00

Solution 2

I resolved actually shutdown must be call before network stream closed.
Thanks Rahul

Posted 30-Jun-14 23:51pm

Muhammad Amman

Comments

Rahul VB 1-Jul-14 7:16am

Dont thank me friend. Its you who has done it. I just backed you.

Good....its Gooood !!!!