RAD Studio VCL Reference
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Get or set object ownership.
property OwnsObjects: Boolean;
__property Boolean OwnsObjects;
OwnsObjects gets or sets whether objects in the queue are owned by the queue or not. If entries are owned, when an entry object is removed from the queue, the entry object is freed. Create initializes this property.
Delphi Examples:
{ This example demonstrates the usage of the generic TObjectQueue class. } type { Declare a new object type } TNewObject = class private FName: String; public constructor Create(const AName: String); destructor Destroy(); override; end; { TNewObject } constructor TNewObject.Create(const AName: String); begin FName := AName; end; destructor TNewObject.Destroy; begin { Show a message whenever an object is destroyed } MessageDlg('Object "' + FName + '" was destroyed!', mtInformation, [mbOK], 0); inherited; end; procedure TForm3.Button1Click(Sender: TObject); var Queue: TObjectQueue<TNewObject>; Button: TButton; begin { Create a new Queue } Queue := TObjectQueue<TNewObject>.Create(); { Set the OwnsObjects to true - the Queue will free them automatically } Queue.OwnsObjects := true; { Enqueue some items up the Queue } Queue.Enqueue(TNewObject.Create('One')); Queue.Enqueue(TNewObject.Create('Two')); Queue.Enqueue(TNewObject.Create('Three')); { Dequeue an instance of TNewObject class. Destructor show be called because we have set the OwnsObjects to true! } Queue.Dequeue(); { Destroy the Queue completely - more messageboxes will be shown } Queue.Free; end;
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