Windows Phone 學習 保存文件到本手機上

   <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
            <StackPanel>
                <TextBlock>鈴聲標題：</TextBlock>
                <TextBox Name="txtName"/>
                <CheckBox Name="ckbShare" Content="與其它應用程序共享" IsChecked="False"/>
                <Button Content="確定" Click="OnOK"/>
            </StackPanel>
        </Grid>

 SaveRingtoneTask MyTask = null;
        // 構造函數
        public MainPage()
        {
            InitializeComponent();
            MyTask = new SaveRingtoneTask();
            MyTask.Completed += new EventHandler<TaskEventArgs>(MyTask_Completed);
        }

        void MyTask_Completed(object sender, TaskEventArgs e)
        {
            if (e.Error != null)
            {
                MessageBox.Show("錯誤：\n" + e.Error.Message);
                return;
            }
            switch (e.TaskResult)
            {
                case TaskResult.Cancel:
                    break;
                case TaskResult.None:
                    break;
                case TaskResult.OK:
                    MessageBox.Show("保存成功。");
                    break;
                default:
                    break;
            }
        }

        private void OnOK(object sender, RoutedEventArgs e)
        {
            if (txtName.Text == "")
            {
                return;
            }
            MyTask.DisplayName = txtName.Text;
            if (this.ckbShare.IsChecked.HasValue)
            {
                MyTask.IsShareable = this.ckbShare.IsChecked.Value;
            }
            MyTask.Source = new Uri("appdata:/test.mp3");
            MyTask.Show();
        }