通过 TCP/IP 将 Delphi 客户端应用程序连接到服务时出现问题

Question

我正在尝试将用 Delphi 编写的客户端应用程序连接到使用 TCP/IP 的服务器上运行的服务。该服务也是用 Delphi 编写的，并使用 TIdTCPServer 来监听连接。当客户端应用程序尝试连接到服务时，我收到错误“连接被拒绝”。该服务似乎工作正常，所有侦听和进一步步骤（通过 ADO 连接到数据库）都在线程中进行。

这是我已经检查过的：

• 客户端应用程序正在使用正确的 IP 地址和端口号进行连接。

class function OperationThread.DefaultHost: string;
begin
  Result := '127.0.0.1';
end;
class function OperationThread.DefaultPort: Integer;
begin
  Result := 5000;
end;

• 我已确保客户端和服务器都使用相同的协议（TCP）。 服务器代码（服务）：

procedure ServiceController(CtrlCode: DWord); stdcall;
begin
  MyService.Controller(CtrlCode);
end;

function TTestService2.GetServiceController: TServiceController;
begin
  Result := ServiceController;
end;

procedure TTestService2.ServiceExecute(Sender: TService);
begin
  while not Terminated do
  begin
    ServiceThread.ProcessRequests(False);
    TThread.Sleep(1000);
  end;
end;

procedure TTestService2.ServiceStart(Sender: TService; var Started: Boolean);
begin
  try
    FBackgroundThread := TBackgroundThread.Create(
      ADOConnection1, DBemployesConnection, ADOQuery1, ADOQuery2, ADOQuery3, IdTCPServer1);
    FBackgroundThread.Start;
    Started := True;
  except
    on E: Exception do
    begin
      Started := False;
    end;
  end;
end;

procedure TTestService2.ServiceStop(Sender: TService; var Stopped: Boolean);
begin
  try
    if Assigned(FBackgroundThread) then
    begin
      FBackgroundThread.Terminate;
      FBackgroundThread.WaitFor;
      FreeAndNil(FBackgroundThread);
    end;

    Stopped := True;
  except
    on E: Exception do
    begin
      Stopped := False;
    end;
  end;
end;

procedure TTestService2.ServicePause(Sender: TService; var Paused: Boolean);
begin
  FBackgroundThread.Pause;
  Paused := True;
end;

procedure TTestService2.ServiceContinue(Sender: TService; var Continued: Boolean);
begin
  FBackgroundThread.Continue;
  Continued := True;
end;

以及我在服务中使用的线程代码：

constructor TBackgroundThread.Create(ADOConnection, DBEmployesConnection: TADOConnection;
  ADOQuery1, ADOQuery2, ADOQuery3: TADOQuery; IdTCPServer: TIdTCPServer);
begin
  inherited Create(True);
  FADOConnection := ADOConnection;
  FDBEmployesConnection := DBEmployesConnection;
  FADOQuery1 := ADOQuery1;
  FADOQuery2 := ADOQuery2;
  FADOQuery3 := ADOQuery3;
  FIdTCPServer := IdTCPServer;
  FreeOnTerminate := True;

  FADOConnection.Connected := True;
  FDBEmployesConnection.Connected := True;
  FIdTCPServer.Active := True;
end;
destructor TBackgroundThread.Destroy;
begin
  if Assigned(FADOConnection) then
    FADOConnection.Free;
  if Assigned(FDBEmployesConnection) then
    FDBEmployesConnection.Free;
  if Assigned(FADOQuery1) then
    FADOQuery1.Free;
  if Assigned(FADOQuery2) then
    FADOQuery2.Free;
  if Assigned(FADOQuery3) then
    FADOQuery3.Free;
    FIdTCPServer.Active := False;
  inherited;
end;

procedure TBackgroundThread.Continue;
begin
  FPaused := False;
end;

procedure TBackgroundThread.Execute;
begin
  CoInitialize(nil);
  try
  FIdTCPServer.OnExecute := IdTCPServer1Execute;
    while not Terminated do
    begin
      if not FPaused then
      begin
        // Główne zadania wątku
        // Na przykład przetwarzanie zapytań, jeśli istnieją
      end
      else
      begin
        Sleep(100);
      end;

      Sleep(10);
    end;
    FIdTCPServer.Active := False;
  finally
    CoUninitialize;
  end;
end;

procedure TBackgroundThread.IdTCPServer1Execute(AContext: TIdContext);
var
  Request: string;
  Response: string;
begin
  try
    Request := AContext.Connection.IOHandler.ReadLn;
    ProcessRequest(Request, Response);
    AContext.Connection.IOHandler.WriteLn(Response);
  except
    on E: Exception do
    begin
      Response := '{"status":"error", "message":"Błąd podczas przetwarzania zadania: ' + E.Message + '"}';
      AContext.Connection.IOHandler.WriteLn(Response);
    end;
  end;
end;

procedure TBackgroundThread.Pause;
begin
  FPaused := True;
end;

其余代码并不重要，并且运行良好。

Answer 1

尝试为应用程序的每个步骤和 IdTcpServer 事件添加日志记录，写入日志侦听状态和其他服务器参数。最简单的方法 - 编写简单的控制台应用程序。 另外，您的服务的权限可能存在问题。检查哪个用户正在运行该服务。