'MyThread' does not run. I do not know whether the problem happens on 'DataTransferServiceStart' procedure. I guess the 'DataTransferServiceStart' procedure does not execute. IDE is Delphi XE. Please help me, thank you very much.
Thread's Unit:
unit Unit_MyThread;
interface
uses
Classes, SysUtils;
type
TMyThread = class(TThread)
private
{ Private declarations }
protected
procedure Execute; override;
end;
implementation
procedure TMyThread.Execute;
var
log: TextFile;
logPath: String;
i: Integer;
begin
logPath := 'd:\test.log';
AssignFile(log, logPath);
Append(log);
i := 0;
while not self.Terminated do
begin
Sleep(1);
Writeln(log, IntToStr(i));
if i=10 then
Terminate;
i := i + 1;
end;
CloseFile(log);
end;
end.
Main Service Unit:
unit Unit_main;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, SvcMgr, Dialogs,
ExtCtrls, DB, ADODB, Unit_MyThread;
type
TDataTransferService = class(TService)
DBSrc: TADOConnection;
procedure DataTransferServiceStart(Sender: TService; var Started: Boolean);
procedure DataTransferServiceContinue(Sender: TService; var Continued: Boolean);
procedure DataTransferServicePause(Sender: TService; var Paused: Boolean);
procedure DataTransferServiceStop(Sender: TService; var Stopped: Boolean);
public
function GetServiceController: TServiceController; override;
end;
var
DataTransferService: TDataTransferService;
MyThread: TMyThread;
implementation
{$R *.DFM}
procedure ServiceController(CtrlCode: DWord); stdcall;
begin
DataTransferService.Controller(CtrlCode);
end;
function TDataTransferService.GetServiceController: TServiceController;
begin
Result := ServiceController;
end;
procedure TDataTransferService.DataTransferServiceStart(Sender: TService;
var Started: Boolean);
begin
MyThread := TMyThread.Create(False);
Started := True;
end;
procedure TDataTransferService.DataTransferServiceContinue(Sender: TService;
var Continued: Boolean);
begin
MyThread.Start;
Continued := True;
end;
procedure TDataTransferService.DataTransferServicePause(Sender: TService;
var Paused: Boolean);
begin
MyThread.Suspended := true;
Paused := True;
end;
procedure TDataTransferService.DataTransferServiceStop(Sender: TService;
var Stopped: Boolean);
begin
MyThread.Terminate;
Stopped := True;
end;
end.
Your service is most likely failing to start because you have a TADOConnection
component dropped into your service. You cannot do this in services. Since ADO is COM, you must initialize each thread with CoInitialize(nil)
and CoUninitialize
, and only create/use your database components within this.
uses
ActiveX;
procedure TDataTransferService.DataTransferServiceStart(Sender: TService;
var Started: Boolean);
begin
CoInitialize(nil);
DBSrc:= TADOConnection.Create(nil);
//Initialize and Connect DBSrc
MyThread := TMyThread.Create(False);
Started := True;
end;
procedure TDataTransferService.DataTransferServiceStop(Sender: TService;
var Stopped: Boolean);
begin
MyThread.Terminate;
//Disconnect DBSrc
DBSrc.Free;
CoUninitialize;
Stopped := True;
end;
Read here: Ok to use TADOConnection in threads