delphi-5

问题 I am interested in upgrading a suite of software from ODAC v5 to v8.2.8. One app in particular is causing problems. This application loads one of a set of secondary applications implemented as dlls. LibHandle := LoadLibrary(PChar(dllname)); if LibHandle <> 0 then begin @showForm := GetProcAddress(LibHandle,'ShowMainDllForm'); if (@showForm <> nil) then begin try ShowForm(Application.Handle, @FGlobalVars, 1); The launcher is fine - it has its own database connection, and I can step through the

问题 I want to change the TComboBox so that if I type text into it or manually set the Text property it will trigger the OnChange event. As it is now, doing ComboBox.Text := 'blah' doesn't trigger the OnChange event, nor does typing into the box. I tried creating a TComboBox descendant, which I assume is the right approach, but I'm not really sure how to change what triggers the events. 回答1: To the best of my knowledge, typing into a combo box will result in the OnChange event firing. But it is

问题 This error showed when I tried to select on an empty table in MS SQL Server 2005: "either BOF or EOF is True, or the current record has been deleted". I have used TADOConnection and TADODataSet in Delphi 5 to connect and retrieve data from the database. Conn := TADOConnection.Create(nil); DataSet := TADODataSet.Create(nil); Conn.ConnectionString := 'Provider=SQLOLEDB.1;Password=sa;' + 'Persist Security Info=True;' + 'User ID=user;Initial Catalog=mydb;' + 'Data Source=MYPC\SQLEXPRESS;' + 'Use

问题 Is there a Delphi 5 component that can handle .png files? 回答1: You can use TPNGImage. Download from here Also you can check Delphi PNG libraries here 回答2: TMS and DevExpress both can handle png files. 回答3: I believe the GDI+ delphi interface from progdigy can be used with D5. Its not a simple plug-in to enable PNG support, but on the other hand, it can load a wide variety of file types. So its another option if all else fails. 回答4: I have been using the marvelous Hi Image components for year:

问题 i need to know when my application recieves a WM_SETTINGCHANGE message (formerly known as WM_WININICHANGE). Problem is that the message pump in TApplication sends it down a black hole (default handler) before i can get a chance to see it: procedure TApplication.WndProc(var Message: TMessage); ... begin Message.Result := 0; for I := 0 to FWindowHooks.Count - 1 do if TWindowHook(FWindowHooks[I]^)(Message) then Exit; CheckIniChange(Message); with Message do case Msg of WM_SETTINGCHANGE: begin

问题 I've been trying to track down a memory leak in Jedi VCL's JvHidControllerClass.pas , which i came across this change in the source history: Older revision: constructor TJvHidDeviceReadThread.CtlCreate(const Dev: TJvHidDevice); begin inherited Create(True); Device := Dev; NumBytesRead := 0; SetLength(Report, Dev.Caps.InputReportByteLength); end; Current revision: constructor TJvHidDeviceReadThread.CtlCreate(const Dev: TJvHidDevice); begin inherited Create(False); Device := Dev; NumBytesRead :

问题 using Delphi5. I have an app that starts with windows boot and I would like to Close and Start it on the Hibernate/Wake command. I need to be able to detect if it is coming back from an Hibernate so I can run my app each time. I have a setting in the Registry where the User can choose to run only once per day. I am guessing there is a windows Message or Registry entry that tells the machine that it is going into and coming back from an Hibernate. Thoughts and suggestions? Thanks for looking

问题 Mike Lischke's TThemeServices subclasses Application.Handle , so that it can receive broadcast notifications from Windows (i.e. WM_THEMECHANGED ) when theming changes. It subclasses the Application object's window: FWindowHandle := Application.Handle; if FWindowHandle <> 0 then begin // If a window handle is given then subclass the window to get notified about theme changes. {$ifdef COMPILER_6_UP} FObjectInstance := Classes.MakeObjectInstance(WindowProc); {$else} FObjectInstance :=

问题 i am trying to call EnumSystemLocales in Delphi. For example: { Called for each supported locale. } function LocalesCallback(Name: PChar): BOOL; stdcall; begin OutputDebugString(Name); Result := Bool(1); //True end; procedure TForm1.Button1Click(Sender: TObject); begin EnumSystemLocales(@LocalesCallback, LCID_SUPPORTED); end; The problem is that the callback is only being called once. Note: EnumSystemLocales is returning true, indicating success. The remarks of EnumSystemLocales says that my

问题 i have bit of code that causes an underflow: var t1, t2, delta: DWORD: begin t1 := 0xffffff00; t2 := 0x00000037; delta := (t2 - t1); The subtraction itself does generate an overflow (underflow), but i don't want Delphi to throw an EIntOverflow exception. So i try disabling the generation of overflow checking code by disabling overflow checking: var t1, t2, delta: DWORD: begin t1 := 0xffffff00; t2 := 0x00000037; {$OVERFLOWCHECKS OFF} delta := (t2 - t1); {$OVERFLOWCHECKS ON} Yet even with the