TThread.Queue和TThread.Synchronize的区别

mac2022-06-30  207

TThread.Queue和TThread.Synchronize的区别

效果上:二者的作用都是让业务代码在主线程中执行,差别: Synchronize是阻塞,Queue是非阻塞

代码上 两个方法最终都是调用的 class procedure TThread.Synchronize(ASyncRec: PSynchronizeRecord; QueueEvent: Boolean = False)类方法, 差别 Synchronize则是使用了Thread对象中的FSynchronize对象变量,然后QueueEvent为False来调用TThread.Synchronize类方法,  内部在执行FSynchronize时,创建了事件对象,通过WaitForSingleObject来阻塞执行。  Queue调用是自己创建了一个PSynchronizeRecord, 然后QueueEvent为True来调用TThread.Synchronize类方法,内部则把PSynchronizeRecord放入SyncList列表中,然后退回,并不直接执行PSynchronizeRecord, 那问题来了,在那里执行呢?Delphi在TApplication.Idle方法中执行(最终调用了CheckSynchronize) procedure TForm1.OnReceived(Sender: TObject; AConnection: ICrossConnection; ABuf: Pointer; ALen: Integer); begin TThread.Queue(nil, procedure begin var ms: tstream := TMemoryStream.Create; ms.Size := ALen; ms.Write(ABuf^, ALen); ms.Position := 0; var ms2: tstream := TMemoryStream.Create; tzip.UnZipStream(ms, ms2); //unzip ms.Free; ms2.Position := 0; var pack: tmsgpack := TMsgPack.Create; pack.DecodeFromStream(ms2); case pack.Force('cmd').AsInteger of cmd_query: begin form1.ClientDataSet1.Data := pack.Force('dataset1').AsVariant; form1.ClientDataSet2.Data := pack.Force('dataset2').AsVariant; end; end; pack.Free; end); end;

  

转载于:https://www.cnblogs.com/hnxxcxg/p/11312934.html


最新回复(0)