Question

我的服务器端表单中有一个用户列表，成功登录后的每个用户都会添加到此列表中。我正在使用IdCmdTCPServer来处理连接。对于下一个操作或用户请求，我通过这种方式为每个用户分配了一个唯一ID（我使用了上下文绑定句柄）以进行连接标识：

procedure TForm1.IdCmdTCPServer1CommandHandlers2Command(ASender: TIdCommand);
var                 // Login Command Handler
  sUsername,
  sPassword: string;
begin
  sUsername := ASender.Context.Connection.Socket.ReadLn;
  sPassword := ASender.Context.Connection.Socket.ReadLn;

  if sUsername = sPassword then    // for example!
  begin
    Inc(UsersCount);
    SetLength(Users, UsersCount);

    with Users[UsersCount - 1] do
    begin
      Username := sUsername;
      ID := ASender.Context.Connection.Socket.Binding.Handle;

      ASender.Context.Connection.Socket.WriteLn(IntToStr(ID));
    end;

    Memo1.Lines.Append('User Logged In: ' + sUsername + ' from ' + ASender.Context.
      Connection.Socket.Binding.PeerIP + ' (' + IntToStr(ASender.Context.Connection.
      Socket.Binding.Handle) + ')');
  end
  else
  begin
    ASender.Context.Connection.Socket.WriteLn('-1'); // -1 means username is not mach to password (wrong user or pass error)

    Memo1.Lines.Append('User Login Fails: ' + sUsername + ' from ' + ASender.Context.
      Connection.Socket.Binding.PeerIP + ' (' + IntToStr(ASender.Context.Connection.
      Socket.Binding.Handle) + ')');

    ASender.Context.Connection.Disconnect;
  end;
end;

一切都很好，运营良好。但是当一个用户 - 因为各种原因 - 与服务器断开连接时，我需要以这种方式从我的列表中删除该用户：

procedure TForm1.IdCmdTCPServer1Disconnect(AContext: TIdContext);
var
  i,
  UserID: Integer;
begin
  UserID := AContext.Connection.Socket.Binding.Handle;

  Memo1.Lines.Append('Disconnected from ' + AContext.Binding.PeerIP + ':' +
    IntToStr(UserID));


  // eliminating user from list
  i := 0;
  while i < UsersCount do
    if Users[i].ID = UserID then
    begin
      Users[i].ID := -11; // ignore this user in next user operations
      Break;
    end
    else
      Inc(i);
end;

问题在于，当上下文连接断开连接时，Handle属性将自动分配-1！我现在无法检测哪个用户连接正在断开连接！

有没有想法检测断开用户上下文的句柄？

如何检测TCP连接中哪个客户端断开连接？

0 个答案: