Delphi属性需要一个常量参数吗？如果是这样,为什么？

program AttributesTestProgram;
{$APPTYPE CONSOLE}
uses
  SysUtils,Classes,RTTI;

type

  TDisplayTextAttribute = class(TCustomAttributE)
  private
    FDisplayText: String;
  public
    constructor Create(aDisplayText: String);
    property DisplayText: String read FDisplayText write FDisplayText;
  end;

constructor TDisplayTextAttribute.Create(aDisplayText: String);
begin
  FDisplayText := aDisplayText;
end;

function GetFirstName: String;
begin
  Result := 'First Name';
end;


type
  TCustomer = Class(TObject)
  private
    FFirstName: String;
    FLastName: String;
    FStreetAddress: String;
    FZIP: String;
    FState: String;
    FCity: String;
    FPhone: String;
  published
    [TDisplayTextAttribute(GetFirstName)]
    property FirstName: String read FFirstName write FFirstName;
  end;

begin
  // Code that does the work removed for clarity....
  Readln;
end.

我很自然地想知道为什么这个错误无法编译：

[DCC Error] AttributesTestProgram.dpr(40): E2026 Constant expression expected

我认为它与属性必须在编译器时间绑定的想法有关,或者沿着那些行绑定.

因此,我的问题是这样的：

有没有办法在这里“击败系统”并获得属性中的那个点的运行时值？