How to delete data in Mobile Services - Windows Phone (Windows Azure)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using myPhoneApp.Resources;

using Microsoft.WindowsAzure.MobileServices;
using Newtonsoft.Json;

namespace myPhoneApp
{

    public class MyMember
    {
        public int Id { get; set; }

        [JsonProperty(PropertyName = "username")]
        public string Username { get; set; }

        [JsonProperty(PropertyName = "password")]
        public string Password { get; set; }

        [JsonProperty(PropertyName = "name")]
        public string Name { get; set; }

        [JsonProperty(PropertyName = "tel")]
        public string Tel { get; set; }

        [JsonProperty(PropertyName = "email")]
        public string Email { get; set; }

    }

    public partial class MainPage : PhoneApplicationPage
    {

        private MobileServiceCollection<MyMember, MyMember> items;
        private IMobileServiceTable<MyMember> memberTable = App.MobileService.GetTable<MyMember>();

        // Constructor
        public MainPage()
        {
            InitializeComponent();
        }

        private async void RefreshMemberItems()
        {
            try
            {
                items = await memberTable.ToCollectionAsync();
            }
            catch (MobileServiceInvalidOperationException e)
            {
                MessageBox.Show(e.Message, "Error loading items", MessageBoxButton.OK);
            }

            myListItems.ItemsSource = items;
        }

        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            RefreshMemberItems();
        }

        private async  void ClickDelete(object sender, RoutedEventArgs e)
        {
            Button btnDel = (Button)e.OriginalSource;
            if (MessageBox.Show("Are you sure?", "Delete ", MessageBoxButton.OKCancel) == MessageBoxResult.OK)
            {

                //** Get Item for Delete ***/
                items = await memberTable
                .Where(memberItem => memberItem.Id == Convert.ToInt32(btnDel.Tag.ToString()))
                .ToCollectionAsync();
                
                //*** Delete ***/
                MyMember member = items[0];
                await memberTable.DeleteAsync(member);
                RefreshMemberItems();

                MessageBox.Show("Delete Completed.", "Result", MessageBoxButton.OK);

            }

        }

    }

}