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Tobject - the base class type that is ancestor to all other classes

type TObject = class constructor Create; ... ... destructor Destroy; virtual; end; Description The TObject type defines the base class type. It is the oldest grandparent of all classes - every class is ultimately derived from TObject. Because of this, every object inherits the methods of TObject. The TObject methods fall into two categories - class and non-class. When prefixed by the keyword Class, a method may be called in both an object of the class, and in the class itself. Such a static method cannot access any class fields because a class has no data itself - only instantiated classes - objects - have data. Some key Class (static) methods: function ClassName Gives the class name as a string ClassParent Gives the class parent name ClassInfo Gives class Run Time info InstanceSize Size of class object in bytes NewInstance Creates a new class object Some key Object methods: Create Empty object creator Free Calls Destroy for a non-nil object ref Destroy Releases object storage AfterConstruction Called after construction BeforeDestruction Called before destruction Related commands Class Starts the declaration of a type of object class Printer Returns a reference to the global Printer object Example code : Using TObject methods inherited in a TForm subclass begin // The unit form was derived from TObject. // So we can use methods of TObject: ShowMessage('Form1 object class name = '+ Form1.ClassName); ShowMessage('Form1 object class parent name = '+ Form1.ClassParent.ClassName); ShowMessage('Form1 object instance size = '+ IntToStr(Form1.InstanceSize)); // And now on TObject itself ShowMessage('TObject class name = '+ TObject.ClassName); ShowMessage('TObject instance size = '+ IntToStr(TObject.InstanceSize)); end; Show full unit code Form1 object class name = TForm1 Form1 object parent class name = TForm Form1 object instance size = 764 TObject class name = TObject TObject instance size = 4