Delphi Indy 10断开连接问题

Question

What i am doing: My server sends data by going through the context list and after it locks on to the specific client it sends that client data, and it expects a reply which we handle in this connection timer. I understand that using a thread would be a better way to do this but this is what i went with.

Here is my problem: I request get connection info and it works fine, the socket writes line getstring data 1 throught 8 but when i write 'Hello' it does not respond with any data it just disconnects the client.

Any help would be greatly appreciated been trying to figure this out for 2 days or so. Thanks in advance!

Here is my code:

procedure TForm1.CommandTimerTimer(Sender: TObject);
var
sl:Tstringlist;
Command: String;
begin
  if clientsocket.IOHandler.InputBufferIsEmpty then
  begin
    clientsocket.IOHandler.CheckForDataOnSource(10);
    if clientsocket.IOHandler.InputBufferIsEmpty then Exit;
  end;
  Command := clientsocket.IOHandler.ReadLn();
  sl:= Tstringlist.Create;
  sl.Delimiter:= '|';
  sl.StrictDelimiter:=true;
  sl.DelimitedText:= Command;
  if sl[0] = 'did i get data' then
  begin
   showmessage('Yea I got Data');
  end;


if sl[0] = 'BroadCasted Message' then
begin
Clientsocket.IOHandler.write('data');
showmessage(sl[1]); // This is data sent from my server to this client, in order to manage the data I have created a Tstringlist and delimited it out by '|'. 
end;
if sl[0] = 'hello' then
begin
  clientsocket.IOHandler.write('data');
end;
if sl[0] = 'Get Connection Info' then
begin
// This part
clientsocket.IOHandler.writeln('Newconnection' + '|' + 'string data 1'  + '|' + 'string data 2' + '|' + 'string data 3' + '|'+ 'string data 4'+'|' + 'string data 5'+'|'+'string data 6'+'|'+'string data 7'+'|'+'string data 8');
end;

if sl[0] = 'Reconnect' then
begin
commandtimer.Enabled:=false;
Connectiontimer.Enabled:=true; // This is a timer that constantly checks and keeps the TidTCPclientsocket connected with my server as this is a Reverse connection Protocol.
Exit;
end;
commandtimer.enabled:=true;
end;

Answer 1

Remy Thank you for the quick reply, My friend and I are working on this project together and shortly after posting this question we both quickly determined the true issue we where having and we have Fixed it!

The Fixed code for anyone who needs it:

Client Side:(Tidtcpclient)

     procedure TForm1.CommandTimerTimer(Sender: TObject);
        var
        sl:Tstringlist;
        Command: String;
        begin
            if clientsocket.IOHandler.InputBufferIsEmpty then
        begin
            clientsocket.IOHandler.CheckForDataOnSource(10);
            if clientsocket.IOHandler.InputBufferIsEmpty then Exit;
          end;
          Command := clientsocket.IOHandler.ReadLn();
          sl:= Tstringlist.Create;
          sl.Delimiter:= '|';
          sl.StrictDelimiter:=true;
          sl.DelimitedText:= Command;
          if sl[0] = 'Get Connection Info' then
          begin
      clientsocket.IOHandler.writeln('String Data 1' + '|' + 'String Data 2'+ '|' + 'String     Data 3'+ '|' + 'String Data 4' + '|'+ 'String Data 5'+'|' + 'String Data 6'+'|'+'String Data 7'+'|'+'String Data 8'+'|'+'String Data 9' + '|' + 'String Data 10' + '|' + 'String Data 11');
end
else
if sl[0] = 'hello' then
begin
showmessage('I got Hello');
clientsocket.IOHandler.writeln('Some Data');
end;
if sl[0] = 'PING!' then
begin
clientsocket.IOHandler.WriteLn('PINGBACK!');
end;

commandtimer.enabled:=true;
end;

Server Side: (TidTCPserver) OnExecute Event Procedure

procedure TForm1.ServersocketExecute(AContext: TIdContext);
Var
sl:Tstringlist;
listitem:Tlistitem;  // This is for a Tlistview where we are adding connection information
Data:String;
Begin
data:= acontext.connection.iohandler.readln(); 
sl:= Tstringlist.create;
sl.delimiter:= '|';
sl.delimitedtext:= data;

    If sl[0] = 'String Data 1' then
begin
listitem:= listview1.items.add;
listitem.caption:= acontext.binding.peerip;
listitem.subitems.add(sl[2]);
listitem.subitems.add(sl[3]);
listitem.subitems.add(sl[4]);
listitem.subitems.add(sl[5]);
listitem.subitems.add(sl[6]);
listitem.subitems.add(sl[7]);
listitem.subitems.add(sl[8]);
listitem.subitems.add(sl[9]);
listitem.subitems.add(sl[10]);

after we add items to the listview component we then go into our own ping method.

Allow me to show everyone what the problem was: 

we recived commands based on the FIRST string received by the clientsocket IE:

If sl[0] = 'Command sent by Client' then
begin

end;

and we kept it going on and on and on IE: 

If sl[0] = 'Command sent by Client' then
begin

end;
If sl[0] = 'Command sent by Client' then
begin

end;

The problem with this is that we cannot allow this code to run on and on like this otherwise the socket hangs and disconnects.

The fix was Simple   Example:

If sl[0] = 'Command sent by Client' then
begin
// Do what we have to do in this instance of receiving a Command and then Exit the sub / Procedure.
exit;
end;

If sl[0] = 'Command sent by Client' then
begin
// do what we got to do in here
Exit; // DON'T forget the exit statement or code runs on and will hang the socket. 
end;

I hope this Example helps anyone else whom is having issues with random disconnections while using indy sockets, lol its usually the programmers fault not the component set he or she is choosing to use.

I'm sorry if this Example code is unreadable this is my first time posting on this site and I'm sure that in future posts I will strive to properly format my comments Ect... Ect...

Also I would like to add for anyone whom is trying to receive data like this on the client side that it would be best best to create your own background worker thread to listen for incoming connections from a TidTCPserver socket. I understand that the timer is bad programming practice and in fact my friend and I will switch it over to a separate thread soon.

Remy once again I think you for your quick reply! Much appreciated sir.