delphi 实现智能指针

Delphi 中可以使用接口来实现智能指针。具体实现方法可以参考以下代码：

type
IMyInterface = interface
['{12345678-1234-1234-1234-1234567890AB}']
procedure DoSomething;
end;

TMyObject = class(TInterfacedObject, IMyInterface)
public
procedure DoSomething;
end;

TMySmartPointer = record
private
FPointer: IMyInterface;
public
class operator Implicit(const AObject: TMyObject): TMySmartPointer;
procedure Free;
function Get: IMyInterface;
end;

implementation

{ TMyObject }

procedure TMyObject.DoSomething;
begin
// Do something
end;

{ TMySmartPointer }

class operator TMySmartPointer.Implicit(const AObject: TMyObject): TMySmartPointer;
begin
Result.FPointer := AObject;
end;

procedure TMySmartPointer.Free;
begin
FPointer := nil;
end;

function TMySmartPointer.Get: IMyInterface;
begin
Result := FPointer;
end;

使用时可以这样：

var
SmartPtr: TMySmartPointer;
begin
SmartPtr := TMyObject.Create;
SmartPtr.Get.DoSomething;
SmartPtr.Free;
end;

这样就可以避免手动管理对象的生命周期，达到智能指针的效果。