为何该句property Staff_Code:WideString read GetStaff_Code;提示InCompatible Types?(0分)

type
TLogin = class(TRemoteDataModule, ILogin)
private
{ Private declarations }
protected
class procedure UpdateRegistry(Register: Boolean;
const ClassID, ProgID: string);
override;
function OldPwd_To_NewPwd(const OldPwd: WideString): WideString;
safecall;
function sp_get_username(const i_duty_office_code,
i_staff_code: WideString): WideString;
safecall;
function GetStaff_Code(const GetAreaCode,
EdStaff_Code: WideString): WideString;
safecall;
function GetPassWord(const edPassWord: WideString): WideString;
safecall;
public
{ Public declarations }
FCount: Integer;
//登录记数
// rAreaCode : TRegistry;
IfLogSuc:boolean;//是否登录成功
property Staff_Code: WideString read GetStaff_Code;
property PassWord: WideString read GetPassWord;
property ClickOk: Boolean read FClickOk write SetClickOk;
end;

作为属性调用的函数不要带形参

接受答案了.