i have a custom component that uses the ParentFont. During construction of my component, i can see that initially the component's font is set to the default MS Sans Serif: constructor TCustomWidg...

We've got this large application written in Delphi 5, and development is ongoing to this day. There is research going on into migrating to newer versions, but so far there is no success, as some 3r...

How can I simulate an OnDestroy event for a TFrame in Delphi? I naively added a constructor and destructor to my frame, thinking that is what TForm does: TframeEditCustomer = class(TFrame) ... pub...

Here's two simple classes, initially both have no keywords (virtual, overload, override, reintroduce): TComputer = class(TObject) public constructor Create(Teapot: Integer); end; TCellPhone = cl...

Today Recently on Stackoverflow i learned that: reintroduce is used to hide ancestor constructors reintroduce is used to show ancestor constructors i've been trying to make sense of it all, so ...

Update: The example i originally had was kind of complex. Here's a simple 8 line example that explains everything in one code block. The following does not compile gives a warning: TComputer = cla...

Is there at way, at runtime, to find all classes that descend from a particular base class? For example, pretend there is a class: TLocalization = class(TObject) ... public function GetLanguageN...

I'm using a custom gauge, based on the example that came with Delphi (5 Enterprise). For those that don't know, it's like a smooth progress bar, but displays the percentage or value in the centre (...

It is possible to declare enums with custom values in Delphi 5 like this?: type MyEnum = (meVal1 = 1, meVal2 = 3); // compiler error Thanks!

Is there a Delphi 5 component that can handle .png files?

i have an object which delegates implementation of a particularly complex interface to a child object. This is exactly i think is the job of TAggregatedObject. The "child" object maintains a weak r...

i profiled a portion of my application using the Delphi Sampling Profiler. Like most people, i see a majority of the time spent inside ntdll.dll. Note: i turned on the options to ignore Applicat...

Consider: const clHotlight: TColor = $00FF9933; clLink = clHotLight; //alias of clHotlight [Error] file.pas: Constant expression expected and the alternate wording that works: const clHot...

How do i run TestCase's from the IDE? i created a new project, with a single, simple, form: unit Unit1; interface uses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,...

Microsoft already says, in the documentation for GetTickCount, that you could never compare tick counts to check if an interval has passed. e.g.: Incorrect (pseudo-code): DWORD endTime = GetTickCou...

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 (underf...

What is TApplication.Handle? Where does it come from? Why does it exist? And most importantly: why do all forms have it as their parent window handle? The Delphi help says: TApplication.Handle P...

I'm using the Win32 CreateProcess function to perform a call to an external executable. The executable returns a string. Is there a way I can capture and interrogate the returned string after call...

I work on a large project in Delphi 5. Today, after merging two branches of the app together, one of the hundreds of units, UnitMain (the main form's unit, would you guess) stopped recognizing the ...