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 stack are owned by the stack or not. If entries are owned, when an entry object is removed from the stack, the entry object is freed. Create initializes this property.
Delphi Examples:
{ This example demonstrates the usage of the generic TObjectStack 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 Stack: TObjectStack<TNewObject>; Button: TButton; begin { Create a new stack } Stack := TObjectStack<TNewObject>.Create(); { Set the OwnsObjects to true - the stack will free them automatically } Stack.OwnsObjects := true; { Push some items up the stack } Stack.Push(TNewObject.Create('One')); Stack.Push(TNewObject.Create('Two')); Stack.Push(TNewObject.Create('Three')); { Pop an instance of TNewObject class. Destructor show be called because we have set the OwnsObjects to true! } Stack.Pop(); { Destroy the stack completely - more messageboxes will be shown } Stack.Free; end;
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