delphi property read writer 如何使用

type  TMyClass = class(TObject)  private    FMyName: string;    FMyAge: Integer;    procedure SetAge(age: Integer);    function GetAge(): Integer;  published    property MyName: string read FMyName write FMyName;    property MyAge: Integer read GetAge write SetAge;  end;

procedure TMyClass.SetAge(age: Integer);begin  if (age < 0) or (age > 200) then    ShowMessage(‘当前设置的年龄数值: ‘ + IntToStr(age) + ‘不是有效的年龄数值‘)  else FMyAge := age;end;

function TmyClass.GetAge: Integer;begin  Result := FMyAge;end;

// 测试procedure TForm1.Button1Click(Sender: TObject);var  ta: TMyClass;begin  ta := TMyClass.Create;  ShowMessage(‘myname:‘ + ta.MyName + ‘, myage:‘ + IntToStr(ta.MyAge));  ta.MyName := ‘Tom‘;  ta.MyAge := -10;  ShowMessage(‘myname:‘ + ta.MyName + ‘, myage:‘ + IntToStr(ta.MyAge));  ta.MyAge := 22;  ShowMessage(‘myname:‘ + ta.MyName + ‘, myage:‘ + IntToStr(ta.MyAge));  ta.free;end;