开发环境Delphi XE10
1 unit Unit1; 2 3 interface 4 5 uses 6 Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics, 7 Vcl.Controls, Vcl.Forms, Vcl.Dialogs, System.RTTI, Vcl.StdCtrls; 8 9 type 10 TForm1 = class(TForm) 11 Button1: TButton; 12 procedure Button1Click(Sender: TObject); 13 private 14 { Private declarations } 15 public 16 { Public declarations } 17 end; 18 type 19 TMyAttribute = class(TCustomAttribute) 20 private 21 FValue: string; 22 public 23 constructor Create(v: string); //带RTTI信息的Attributes时，必须要实现自定义的构造器 24 25 property Value: string Read Fvalue Write FValue; 26 end; 27 //然后就可以用来注释了，简单的注释操作如下 28 [TMyAttribute('Msg')] 29 MyRec = record 30 R_str:string; 31 end; 32 var 33 Form1: TForm1; 34 35 implementation 36 37 {$R *.dfm} 38 function GetMyRecAttr: string; 39 var 40 LContext: TRttiContext; 41 LType: TRttiType; 42 LAttr: TCustomAttribute; 43 begin 44 LContext := TRTTIContext.Create; //创建上下文对象 45 LType := LContext.GetType(TypeInfo(MyRec));//获取MyRec的类型信息 46 try 47 for LAttr In LType.GetAttributes() do //遍历MyRec中的Attributes 48 if LAttr is TMyAttribute then 49 ShowMessage(TMyAttribute(LAttr).value); 50 except 51 ShowMessage('读取失败'); 52 end; 53 end; 54 { TMyAttribute } 55 56 constructor TMyAttribute.Create(v: string); 57 begin 58 FValue:='AAAAAAAAAAA+'+v; 59 end; 60 61 procedure TForm1.Button1Click(Sender: TObject); 62 begin 63 GetMyRecAttr; 64 end; 65 66 end.
1 object Form1: TForm1 2 Left = 0 3 Top = 0 4 Caption = 'Form1' 5 ClientHeight = 130 6 ClientWidth = 288 7 Color = clBtnFace 8 Font.Charset = DEFAULT_CHARSET 9 Font.Color = clWindowText 10 Font.Height = -11 11 Font.Name = 'Tahoma' 12 Font.Style = [] 13 OldCreateOrder = False 14 Position = poDesktopCenter 15 PixelsPerInch = 96 16 TextHeight = 13 17 object Button1: TButton 18 Left = 96 19 Top = 48 20 Width = 75 21 Height = 25 22 Caption = 'Button1' 23 TabOrder = 0 24 OnClick = Button1Click 25 end 26 end
