Questions about the different Scopes/Visibilities of variables in a Delphi Unit -


lets have delphi unit:

unit unit1;  interface  uses   winapi.windows, winapi.messages, system.sysutils, system.variants, system.classes, vcl.graphics,   vcl.controls, vcl.forms, vcl.dialogs, vcl.stdctrls, vcl.extctrls;  type   tform1 = class(tform)      private     { private-deklarationen }   public     { public-deklarationen }   end;  var   form1: tform1;  implementation  {$r *.dfm}  var   nummer:integer;

i understood there public interface-section , private implementation-section.

functions , procedures defined in public-section can used ohter units.

functions , procedures defined in private-section can used in unit.

but variables after var in interface-section global variables? if yes there difference global variables in public? , difference between variables defined after implementation , ones under private?

  • the variables after var in interface section become accessible use global in unit 'uses' unit.
  • the vars defined outside of class have 1 value shared across instances of class, changing variable in 1 object call affect variable objects of class type. if define var inside class definition, each object have own version of variable.

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