TBase=class

public

procedure aaaa();

procedure doaaaa();virtual;

end;

procedure TBase.aaaa()

begin

    doaaaa();

end;

procedure TBase.doaaaa();

begin

     a.function;

end;

--------------------------------------------------

TChild=class(TBase)

public

procedure doaaaa();override;

end;

procedure TChile.doaaaa();

begin

b.function;

end;

 

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调用时,TClild 调用aaaa(),将执行b.function;