About Methods

Within a class declaration, methods appear as procedure and function headings, which work like forward declarations. Somewhere after the class declaration, but within the same module, each method must be implemented by a defining declaration. For example, suppose the declaration of TMyClass includes a method called DoSomething:


TMyClass = class(TObject) procedure DoSomething; end;

A defining declaration for DoSomething must occur later in the module:

procedure TMyClass.DoSomething; begin end;

While a class can be declared in either the interface or the implementation section of a unit, defining declarations for a class' methods must be in the implementation section.

In the heading of a defining declaration, the method name is always qualified with the name of the class to which it belongs. The heading can repeat the parameter list from the class declaration; if it does, the order, type and names of the parameters must match exactly, and if the method is a function, the return value must match as well.

Method declarations can include special directives that are not used with other functions or procedures. Directives should appear in the class declaration only, not in the defining declaration, and should always be listed in the following order:

reintroduce; overload; binding; calling convention;abstract; warning where binding is virtual, dynamic, or override; calling convention is register, pascal, cdecl, stdcall, or safecall; and warning is platform, deprecated, or library.

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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