THiAsmClass = class(TDebug)   
   private
     ProgressW:integer;
     ProgressR:integer;
     FAbort: Boolean;
....
   public
     procedure doAbort(var _Data:TData; Index:word);

....


procedure THiAsmClass.DoTest;
...
begin
...
  FAbort := False;
  for i := 1 to size do
  begin
    ReadFile(h, blk^, 1024*1024, rd, nil);  
    ProgressR :=i;
    if FAbort then Break;
  end;
....
end;

procedure THiAsmClass.doAbort(var _Data:TData; Index:word);
begin
  FAbort := True;
end;