拖管记录

拖管记录

DELPHI10.4开始支持 拖管记录。

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unit Unit1;   interface   uses   Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,   Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;   type   TMyRecord = record     Value: Integer;     class operator Initialize (out Dest: TMyRecord);     class operator Finalize(var Dest: TMyRecord);   end;   type   TForm1 = class(TForm)     Memo1: TMemo;     Button1: TButton;     procedure Button1Click(Sender: TObject);   private     { Private declarations }   public     { Public declarations }   end;   var   Form1: TForm1;   implementation   {$R *.dfm}   class operator TMyRecord.Initialize (out Dest: TMyRecord); begin   Dest.Value := 10;   form1.Memo1.Lines.Add('created' + IntToHex (Integer(Pointer(@Dest)))); end;   class operator TMyRecord.Finalize(var Dest: TMyRecord); begin   form1.Memo1.Lines.Add('destroyed' + IntToHex (Integer(Pointer(@Dest)))); end;   procedure TForm1.Button1Click(Sender: TObject); begin   var r: TMyRecord;   memo1.Lines.Add(r.Value.ToString); end;   end.

　　测试：

created0019F398
10
destroyed0019F398