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TObjectQueue.OwnsObjects Property

Get or set object ownership.

Pascal
property OwnsObjects: Boolean;
C++
__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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