5.2 Fields

Object Fields are like record elds. They are accessed in the same way as a record eld would be accessed : by using a qualied identier. Given the following declaration:

Type TAnObject = Object
       AField : Longint;
       Procedure AMethod;
       end;
Var AnObject : TAnObject;

then the following would be a valid assignment:

AnObject.AField := 0;

Inside methods, elds can be accessed using the short identier:

Procedure TAnObject.AMethod;
begin
  ...
  AField := 0;
  ...
end;

Or, one can use the self identier. The self identier refers to the current instance of the object:

Procedure TAnObject.AMethod;
begin
  ...
  Self.AField := 0;
  ...
end;

One cannot access elds that are in a private section of an object from outside the objects' methods. If this is attempted anyway, the compiler will complain about an unknown identier. It is also possible to use the with statement with an object instance:

With AnObject do
  begin
  Afield := 12;
  AMethod;
  end;

In this example, between the begin and end, it is as if AnObject was prepended to the Afield and Amethod identiers. More about this in section 9.2.7, page 333

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