Question

我使用Indy和Lazarus编写套接字应用程序。这是我的代码如下。套接字连接正确，但在向服务器发送数据包时，它没有收到任何内容。我肯定错过了什么。谢谢！

procedure TSocket.IdTCPServer1Execute(AContext: TIdContext);
var
  Socket_Receive_Buffer: TIdBytes;
  Socket_Input_Length: integer;

begin
  with AContext.Connection do
  begin
    IOHandler.ReadBytes(Socket_Receive_Buffer, 1024, False);
    ShowMessage('Getting bytes');
    Socket_Input_Length := Length(Socket_Receive_Buffer);
    if Socket_Input_Length > 0 then
    begin
      Writeln('received something: nb bytes = '+IntToStr(Socket_Input_Length));
    end;
  end;
end;

function TSocket.Open: boolean;

begin
  if Settings.SocketModeRadioGroup.ItemIndex = 0 then
  begin
    IdTcpServer1 := TIdTCPServer.Create(nil);
    IdTCPServer1.OnExecute := @IdTCPServer1Execute;
    IdTCPServer1.OnConnect := @IdTCPServer1Connect;
    IdTCPServer1.OnDisconnect := @IdTCPServer1Disconnect;
    IdTcpServer1.DefaultPort := StrToInt(Settings.SocketPortEdit.Text);
    IdTcpServer1.MaxConnections := 1;
    IdTCPServer1.Bindings.Add.IPVersion := Id_IPv4;
    IdTcpServer1.Active := True;
    Writeln('Server started. Listening for messages');
  end
  else
  begin
    ShowMessage('Client');

    IdTcpClient1 := TIdTCPClient.Create(nil);
    //IdTcpClient1.DefaultPort := StrToInt(Settings.SocketPortEdit.SelText);
  end;
end;

Answer 1

服务器期望每个消息正好接收1024个字节，不多也不少。客户端实际发送的是1024字节吗？我猜不是。 ReadBytes(1024)在完全读取1024个字节之前不会退出，它不会读取更少的字节。如果您需要这种功能，请传递-1而不是1024. ReadBytes(-1)将返回当时可用的任何字节。

Answer 2

最后是工作代码。

procedure TSocket.IdTCPServer1Execute(AContext: TIdContext);
var
  Socket_Receive_Buffer: TIdBytes;
  Socket_Input_Length: integer;
  Input_Buffer: TByteArray;

begin
  with AContext.Connection do
  begin
    IOHandler.ReadBytes(Socket_Receive_Buffer, -1, false);
    Socket_Input_Length := Length(Socket_Receive_Buffer);
    if Socket_Input_Length > 0 then
    begin
      BytesToRaw(Socket_Receive_Buffer,Input_Buffer,Socket_Input_Length);
      Terminal.GuiTerminalPutInput(Input_Buffer, Socket_Input_Length);
    end;
  end;
end;

在Indy / Lazarus中使用ReadBytes

2 个答案: