delphi - check if a inifile is existing or still <nil> in my code sequence -


the following code 

  var ainifile: tinifile;     procedure aspecialevent (ainifile: tinifile );   begin   ....   if (ainifile <> nil)   begin     if fileexists(ainifile.filename)   //  error here ....     begin        ......      end;   end;     end;     //   mainformcode     //   need call procedure tini file not yet created      aspecialevent(ainifile);

fails access violation. infile not nil can not access the filename property. how check more efficient if file valid or not?

the explanation 1 of following:

  1. ainifile has not been initialised , has ill-defined value.
  2. ainifile has been initialised, refers object has been destroyed.
  3. ainifile member of record or class, , implicit self pointer invalid. option seems rather unlikely.

it's impossible diagnose more that, 1 of above reason error.

judging comments, looks have not initialised local variable ainifile. in case item 1 applies. suspect expecting local variables automatically initialised. not case: are delphi variables initialized value default?

if wish nil mean object has not been instantiated, have explicitly initialise ainifile nil.


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