Sending messages between Delphi threads

Thread B sends a message to thread A, SendMessage (thread A handle, MSG, wparam parameter, lparam parameter);

Thread A overrides WndProc (Var message:tmessage);

1 {thread B sends a message}2 UnitThreadunit;3 4 Interface5 6 uses7 Classes, ActiveX, Businessservice, Dialogs, Constant, Windows, Messages, sysutils;8 9 typeTenTupgradeappthread =class(TThread) One   protected A     procedureExecuteOverride; -   Private -Appfiledir:string; the Manualcheck:boolean; -    Public -Mainfromhandle:hwnd;//main thread handle -     Constructor Create(Appfiledir:string; manualcheck:boolean); +   End; -  + Const {0x0400-0x7fff} AWM_UPDATE_UI1 = Wm_user + $1001; atWm_update_ui2 = Wm_user + $1002; -  - var - Upgradeappthread:tupgradeappthread; -  - Implementation in  - ConstructorTupgradeappthread.Create(Appfiledir:string; manualcheck:boolean); to begin +   inherited Create(False); -Self.appfiledir: =Appfiledir; theSelf.manualcheck: =Manualcheck; * End; $ Panax Notoginseng procedureTupgradeappthread.execute; - var theRes:string; + sdata:tcopydatastruct; A begin theFreeonterminate: =True; +   Try -Res: =upgradeapplication (Appfiledir, False); $     ifres ='0'  Then $     begin -       //The full version of the customer update is not detected for DLL update detection -Res: =Upgradedllonline (appfiledir); the     End; - Wuyi     ifres ='0'  Then the     begin -       ifSelf.manualcheck Then Wu       begin -ShowMessage ('Booz Client is the latest version, no need to update! '); About       End; $     End -     Else ifres = bserror_no_servconf Then -     begin -       ifSelf.manualcheck Then A       begin +ShowMessage ('The update server address is empty! '); the       End; -     End $     Else ifres ='2'  Then theSendMessage (Mainfromhandle, Wm_update_ui2,0,0)//sending DLL update messages to the main thread the     Else the     begin the       Try -Sdata.lpdata: =PChar (res); inSendMessage (Mainfromhandle, WM_UPDATE_UI1,0, Cardinal (@sData));//update messages to the mainline Cheng client the       finally the //Freemem (sdata.lpdata); About       End; the     End; the   finally the  +   End; - End; the Bayi End.

1 {thread A receives messages}2 protected3     procedureWndProc (varMessage:tmessage);Override;4 5 //Create thread B6Upgradeappthread: = Tupgradeappthread.Create(Appfiledir, Manualcheck);//will check for updates to be executed on the thread7Upgradeappthread.mainfromhandle: =Self.handle;8 9 Ten procedureTfrmmain.wndproc (varMessage:tmessage);//Receive thread Messages One var A param:tstringlist; - httpclient:tidhttp; -Controlurl, Res:string; theAppPath:string; - cdds:tcopydatastruct; - begin -Res: ="'; +    CaseMessage.msg of -WM_UPDATE_UI1:{Client Update Messages} +       begin ARes: ='Booz Client assistant needs to update to the latest version, need to shut down the client to update, is it updated immediately? '; atCDDs: =pcopydatastruct (message.lparam) ^; -AppPath: =Strpas (PChar (Cdds.lpdata)); -Controlurl: ='/ http'+ ServerIP +':'+ IntToStr (Strtoint (serverport) +2) +'/upgrademainapp?fp='+AppPath; -       End; -WM_UPDATE_UI2:{DLL Update message} -       begin inRes: ='client component Updates detected, the Booz client assistant needs to be restarted to update, is it immediately updated? '; -Controlurl: ='/ http'+ ServerIP +':'+ IntToStr (Strtoint (serverport) +2) +'/controlmainapp?ct=2'; to       End; +   Else -     inherited; the   End; *   ifRes <>"'  Then $   beginPanax Notoginseng     Try -       ifMessageBox (Self.handle, PChar (res),'Ask', mb_iconquestion + Mb_yesno + mb_topmost + mb_defbutton2) = Idyes Then the       begin +Param: = tstringlist.Create; AHttpClient: = Tidhttp.Create; theControlurl: = StringReplace (Controlurl,' ','%20', [Rfreplaceall]); + httpclient.post (Controlurl, param); -       End; $     finally $ Httpclient.free; - param. Free; -     End; the   End; - End;

Sending messages between Delphi threads