IsolatedStorage实现软件登陆时的密码验证

Login.xaml:

public partial class Login : PhoneApplicationPage
    {
        private const string pwd = "pwd";

        public Login()
        {
            InitializeComponent();
            this.Loaded += new RoutedEventHandler(Login_Loaded);
        }

        void Login_Loaded(object sender, RoutedEventArgs e)
        {
            if (!IsolatedStorageSettings.ApplicationSettings.Contains(pwd))
            {
                textBlock.Text = "请设定密码：";
            }
        }

        private void buttonReset_Click(object sender, RoutedEventArgs e)
        {
            textBox.Text = "";
        }

        private void buttonOK_Click(object sender, RoutedEventArgs e)
        {
            if (!IsolatedStorageSettings.ApplicationSettings.Contains(pwd))
            {
                IsolatedStorageSettings.ApplicationSettings[pwd] = textBox.Text;
                IsolatedStorageSettings.ApplicationSettings.Save();
                NavigationService.Navigate(new Uri("/MainPage.xaml", UriKind.Relative));
            }
            else
            {
                if (textBox.Text.Equals(IsolatedStorageSettings.ApplicationSettings[pwd] as string))
                {
                    NavigationService.Navigate(new Uri("/MainPage.xaml", UriKind.Relative));
                }
                else
                {
                    textBlock.Text = "请重新输入：";
                    textBox.Text = "";
                }
            }
        }
    }

MainPage.xaml:

public partial class MainPage : PhoneApplicationPage
    {
        private const string pwd = "pwd";

        // 构造函数
        public MainPage()
        {
            InitializeComponent();
            this.Loaded += new RoutedEventHandler(MainPage_Loaded);
            this.BackKeyPress += new EventHandler<System.ComponentModel.CancelEventArgs>(MainPage_BackKeyPress);
        }

        void MainPage_BackKeyPress(object sender, System.ComponentModel.CancelEventArgs e)
        {
            MessageBoxResult msgRst = MessageBox.Show("要退出到登陆界面吗？", "提示", MessageBoxButton.OKCancel);
            if (msgRst == MessageBoxResult.Cancel)
            {
                e.Cancel = true;
            }
        }

        void MainPage_Loaded(object sender, RoutedEventArgs e)
        {
            textBlock.Text = IsolatedStorageSettings.ApplicationSettings[pwd] as string;

        }

    }