Results 1 to 10 of 10

Thread: Question about lnet :)

  1. #1

    Cool Question about lnet :)

    So I've been playing around with lnet console and I can't manage to receive messages. I can receive and send messages fine with lnet visual but I can only send with lnet console.

    I imagine it has something to do with this line:

    FCon.OnReceive := OnRe;

    I'm thinking that assigning OnReceive to OnRe isn't actually doing what I want. The original code from the example is:

    FCon.OnReceive := @OnRe;

    But that doesn't compile in Lazarus unless you add {$mode objfpc}{$H+} which I can't for my project.

    Anyone have any advice they can give? Any help is appreciated

    Thank you!

  2. #2
    PGD Staff code_glitch's Avatar
    Join Date
    Oct 2009
    Location
    UK (England, the bigger bit)
    Posts
    933
    Blog Entries
    45
    Perhaps try
    Code:
    {$Mode Delphi}
    or
    Code:
    type
       pOnReType = OnReType^;
    I once tried to change the world. But they wouldn't give me the source code. Damned evil cunning.

  3. #3
    Haha awesome signature code_glitch, will try these tricks when I get home. Thank you!

  4. #4
    I tried {$Mode Delphi} and that didn't work.

    I'm not sure what to do with pOnReType = OnReType^; though, could you provide an example for me so I can understand the context its used in?

  5. #5
    Here's the code I'm using:
    {$IFDEF WINDOWS}
    {$R *.res}
    {$ENDIF}
    {$DEFINE STATIC}

    {$Mode Delphi}

    uses
    lnet, crt, classes;

    type
    { TLTCPTest }
    TLTCPTest = class
    private
    FQuit: boolean;
    FCon: TLTcp; // the connection
    { these are all events which happen on our server connection. They are called inside CallAction
    OnEr gets fired when a network error occurs.
    OnRe gets fired when any of the server sockets receives new data.
    OnDs gets fired when any of the server sockets disconnects gracefully.
    }
    procedure OnDs(aSocket: TLSocket);
    procedure OnRe(aSocket: TLSocket);
    procedure OnEr(const msg: string; aSocket: TLSocket);
    public
    message: string;
    received: TStringlist;
    constructor Create;
    destructor Destroy; override;
    end;

    procedure TLTCPTest.OnDs(aSocket: TLSocket);
    begin
    //
    end;

    procedure TLTCPTest.OnRe(aSocket: TLSocket);
    var
    s: string;
    begin
    if aSocket.GetMessage(s) > 0 then
    begin
    message:='Received message "'+s+'"';
    end;
    end;

    procedure TLTCPTest.OnEr(const msg: string; aSocket: TLSocket);
    begin
    //
    end;

    constructor TLTCPTest.Create;
    begin
    FCon := TLTCP.Create(nil);
    FCon.OnError := OnEr;
    FCon.OnReceive := OnRe;
    FCOn.OnDisconnect := OnDs;
    FCon.Timeout := 100;
    end;

    destructor TLTCPTest.Destroy;
    begin
    FCon.Free; // free the connection
    inherited Destroy;
    end;

    procedure netconnect(server, portz: string);
    var
    Address: string;
    Port: Word;
    attempt: integer;
    quitting: boolean;
    begin
    address:=server;
    port:=word(strtoint(portz));
    attempt:=0;
    quitting:=false;
    tcp.FCon.Connect(Address, Port);
    repeat
    tcp.FCon.CallAction;
    attempt:=attempt+1;
    if attempt=9001 then quitting:=true;
    until tcp.fcon.Connected or quitting;
    end;

    procedure netmessage(str: string);
    begin
    tcp.FCon.SendMessage(str+#13#10);
    end;

    Begin
    tcp:=tltcptest.create;
    netconnect('192.168.0.1', '1111');
    netmessage('hello!');
    And after netmessage('hello!'); I use some other code that uses messages received and other stuff.
    Last edited by NickS; 29-08-2011 at 02:38 AM.

  6. #6
    PGD Staff code_glitch's Avatar
    Join Date
    Oct 2009
    Location
    UK (England, the bigger bit)
    Posts
    933
    Blog Entries
    45
    Ah, OnRe is a procedure.... Hmm. I thought it was just a variable and that it was one of those times where the @ trick didn't work for the memory address and thus a pointer to it as a variable type might however that usually doesn't work with a procedure.

    The problem, after looking at the code, is that you are trying to set the variable FCon.OnRecieve to a procedure - which cannot be done. The example is correct in saying that IF FCon.Onrecieve is of type procedure you could tell it the memory address of the procedure with the @.

    Ignoring all of the above, whats the error message the compiler gives exactly? My suggestion coming from a pure FPC perspective would be to do

    Code:
    if FCon.OnRecieve then OnRe;
    However this assumes that FCon.OnRecieve is of type Boolean and that, as the code indicates, OnRe is a procedure. However, this is from a FPC perspective as my lazarus knowledge is very limited.
    I once tried to change the world. But they wouldn't give me the source code. Damned evil cunning.

  7. #7
    Yes OnRe is a procedure so it doesn't return any value. Here is the code for FCon.OnReceive:

    property OnReceive: TLSocketEvent read FOnReceive write FOnReceive;

    I'm not sure how properties work so that's probably why I'm stumped on this


    When I compile with the code being:

    FCon.OnReceive := @OnRe;

    It says: Variable identifier expected.

    I really appreciate your help Code_Glitch, I hope we can sort this issue out because I'm this ->||<- close to having multiplayer for my game

  8. #8
    PGD Staff code_glitch's Avatar
    Join Date
    Oct 2009
    Location
    UK (England, the bigger bit)
    Posts
    933
    Blog Entries
    45
    I read this page: http://wiki.freepascal.org/User_Chan...regular_fields

    My understanding from it is that the 'property' maps onto a variable of some type and that it can be used as a sort of splitter. Ie: The property can be read and it will read from a value and the property can be written to in which case it can write to another value. I only had a skim so I'm not sure how it could apply. I'll think it over and hopefully come up with a solution later this evening - hungry as ever so unable to work on it much right now
    I once tried to change the world. But they wouldn't give me the source code. Damned evil cunning.

  9. #9

  10. #10
    Fixed it just forgot to do FCon.Callaction;

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comodo SSL