原来的实现：http://blog.csdn.net/jankercsdn/article/details/8874469 有许多不完善的地方，使用中进行了一些改动和完善，

unit uHardWorkThread;interfaceusesWindows, Messages, Classes, SysUtils, SyncObjs;constWM_QUIT_HARD_THREAD = WM_USER + 305;  //退出线程typeTHardWorkThread = class(TThread)privateFMsgHandle:THandle;                               //消息目的窗口句柄FErrorCount:Integer;                              //连续错误次数FIsWorking:boolean;                               //是否正在工作FIsSuspending:Boolean;                            //是否正在挂起FQuitEvent:TEvent;                                //退出线程事件FRunEvent:TEvent;                                 //运行事件，有信号表示运行FWorkCompletedEvent:TEvent;                       //工作完成事件, 有信号表示完成FPIsInterrupt:PBoolean;                           //中断protectedfunction  WaitForWorkCompleted(const AWaitTime:Integer):Boolean;        //等待线程工作完成procedure SetupWorkCompleted(AWorkCompleted:Boolean);                   //设置线程工作状态procedure ImmediatelySuspend;                                           //立即挂起,一般继承子孙类内部用procedure Execute; override;procedure DoWorkProc(const APIsInterrupt:PBoolean); virtual; abstract;  //实际的工作过程(虚方法，子类必须实现)publicconstructor Create(AMsgHandle:THandle); virtual;                        //这个句柄注意，当消息目的窗体的Position变化时,窗体的Handle就变了(比如Dock窗体)destructor Destroy; override;procedure StartThread;                                                  //开始线程function  ExitThread(const AWaitTime:Integer):Boolean;                  //退出线程function  SuspendThread(const AWaitTime:Integer):Boolean;               //挂起线程procedure ResumeThread;                                                 //恢复线程property  MsgHandle:THandle read FMsgHandle write FMsgHandle;           //消息句柄property  ErrorCount:Integer read FErrorCount;end;implementation{ THardWorkThread }constructor THardWorkThread.Create(AMsgHandle: THandle);
begininherited Create(True);FMsgHandle:=AMsgHandle;FQuitEvent:=TEvent.Create;FRunEvent:=TEvent.Create;FRunEvent.ResetEvent;FWorkCompletedEvent:=TEvent.Create;FWorkCompletedEvent.SetEvent;New(FPIsInterrupt);FPIsInterrupt^:=False;FErrorCount:=0;FIsWorking:=False;FIsSuspending:=True;//FreeOnTerminate:=True;  //不要自动释放
end;destructor THardWorkThread.Destroy;
beginDispose(FPIsInterrupt);FWorkCompletedEvent.Free;FRunEvent.Free;FQuitEvent.Free;inherited;
end;{
procedure THardWorkThread.DoWorkProc;
beginend;
}
procedure THardWorkThread.Execute;
varMsg:TMsg;
beginwhile True dobeginif PeekMessage(Msg,0,0,0,PM_REMOVE) thenbeginif Msg.message = WM_QUIT_HARD_THREAD thenbeginFQuitEvent.SetEvent;Break;end;end;if FPIsInterrupt^ thenbeginContinue;end;//等待运行FIsSuspending := True;FRunEvent.WaitFor(INFINITE);FIsSuspending := False;//退出时，如果线程挂起，则要恢复线程，然后退出if PeekMessage(Msg,0,0,0,PM_NOREMOVE) thenbeginif Msg.message = WM_QUIT_HARD_THREAD thenContinue;end;if FPIsInterrupt^ thenbeginContinue;end;SetupWorkCompleted(False);          //开始工作tryDoWorkProc(FPIsInterrupt);finallySetupWorkCompleted(True);        //完成工作end;Sleep(100);end;
end;function THardWorkThread.ExitThread(const AWaitTime: Integer): Boolean;
beginResult:=True;FPIsInterrupt^:=True;PostThreadMessage(ThreadID,WM_QUIT_HARD_THREAD,0,0);if FIsSuspending thenResumeThread;//PostThreadMessage(ThreadID,WM_QUIT_HARD_THREAD,0,0);if FQuitEvent.WaitFor(AWaitTime) = wrTimeOut thenResult:=False;
end;procedure THardWorkThread.ImmediatelySuspend;
beginFRunEvent.ResetEvent;//FIsSuspending := True;
end;procedure THardWorkThread.ResumeThread;
beginFRunEvent.SetEvent;//FIsSuspending := False;
end;procedure THardWorkThread.SetupWorkCompleted(AWorkCompleted: Boolean);
beginFIsWorking:=not AWorkCompleted;if AWorkCompleted thenbeginFWorkCompletedEvent.SetEvent;endelsebeginFWorkCompletedEvent.ResetEvent;end;
end;procedure THardWorkThread.StartThread;
beginStart;
end;function THardWorkThread.SuspendThread(const AWaitTime: Integer): Boolean;
beginResult:=False;if FIsSuspending thenbeginResult:=True;endelsebeginif WaitForWorkCompleted(AWaitTime) thenbeginFRunEvent.ResetEvent;FIsSuspending:=True;Result:=True;end;end;
end;function THardWorkThread.WaitForWorkCompleted(const AWaitTime: Integer): Boolean;
beginResult:=True;if FIsWorking thenResult:=FWorkCompletedEvent.WaitFor(AWaitTime) = wrSignaled;
end;end.