Asyncronous Socket Problem

Asyncronous Socket Problem

• Jonas.Lewin

  In The Name of God
  
  hello,
  
  thanks for your response,
  
  in your response you said that instead of sending the socket to the Asynccallbak method we send a class object right but the method that you wanna send to asynccallback got the IAsyncResult argument that's not got any enumeration like UserState please tell me how shoud i do this
  
  Error 1 'System.IAsyncResult' does not contain a definition for 'UserState'
  
  
  thanks
  
  
  
  
  

• deo1979

  You don't need the global variables. The general technique is to create a state class lets say

  class MyState
  {
  Socket s;
  byte[] SendBuffer = new byte[...];
  unsigned long SendOffset
  byte[] ReceiveBuffer = new byte[...];
  unsigned long ReceiveOffset;
  }
  
  and when you post an async operation do something like
  s.BeginReceive(new AsyncCallback(...), MyState m)
  
  In the Callback
  
  you can get the state by using
  
  MyState m = (MyState)IAsyncResuct.UserState

  
  

  
  
  

• Rick Walker

  In The Name of God
  
  hello
  
  my problem solved.
  
  your implementation (total structure) was correct, but that didn't have enough consideration.
  I mean there were some some points that must have been observed.
  
  1- IAsyncResult doesn't have any enumeration like UserState.
  2- if u use define the MyState class object and send it to AsyncCallBack delegate it generates an exception cause you have not referenced it.
  3- if you reference your object but don't fill it with proper data another exception would be raised and tell that the socket in your class is Nothing. so you must fill the object before you send it to AsyncCallBack.
  
  so the proper code would be :
  
  this is the class that you told me but in VB
  -------------------------------------------
  
  
  Public Class MyState
  
  Public s As Socket
  
  Public SendBuffer(1024) As Byte
  
  Public SendOffset As Long
  
  Public ReceiveBuffer(1024) As Byte
  
  Public ReceiveOffset As Long
  
  'any kinda of necessary data can be here
  End Class
  
  '----------------------------------------------------
  'Main primary function ( sck_Accepted_Socket is an accepted socket )
  '-----------------------------------------------------
  
  
  Private Sub btn_Server_Receive_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_Server_Send.Click
  Dim M As New MyState
  M.s = sck_Accepted_Socket
  M.SendBuffer = byt_Buffer
  
  sck_Accepted_Socket.BeginReceive(byt_Buffer, 0, 5, SocketFlags.None, New AsyncCallback(AddressOf Receive_Delegate), M)
  
  txt_Server.Text = Encoding.ASCII.GetString(byt_Buffer, 0, 5)
  MessageBox.Show(Encoding.ASCII.GetString(M.SendBuffer))
  
  End Sub
  
  ------------------------------------------------------
  the receive delegate
  -----------------------------------------------------
  
  Private Sub Receive_Delegate(ByVal iar As IAsyncResult)
  
  Dim M As MyState = iar.AsyncState
  M.s.EndReceive(iar)
  
  End Sub
  
  '----------------------------------------------------
  
  
  'and at last special thanks for your help.
  
  
  
• Asyncronous Socket Problem