private async void ProcessEContactClick(EContactItem selectedItem)
        {
            string content = string.Format("Call or message {0}?\nPress back to cancel.", selectedItem.Name);
            string title   = "Information";

            string[]      cmdString = new string[] { "call", "message" };
            MessageDialog md        = new MessageDialog(content, title);

            md.Commands.Add(new UICommand(cmdString[0]));
            md.Commands.Add(new UICommand(cmdString[1]));

            IUICommand result = await md.ShowAsync();

            if (result == null)
            {
                return;
            }

            string resultString = result.Label;

            if (resultString == cmdString[0])
            {
                // Process call
                Windows.ApplicationModel.Calls.PhoneCallManager.ShowPhoneCallUI(selectedItem.Contact, selectedItem.Name);
            }
            else if (resultString == cmdString[1])
            {
                // Process message
                Windows.ApplicationModel.Chat.ChatMessage chatMsg = new Windows.ApplicationModel.Chat.ChatMessage();
                chatMsg.Recipients.Add(selectedItem.Contact);
                chatMsg.Body = "";
                await ChatMessageManager.ShowComposeSmsMessageAsync(chatMsg);
            }
        }
        /// <summary>
        /// 发送短信
        /// </summary>
        /// <param name="toPhoneNumber">目标电话号码</param>
        /// <param name="body">短信主体</param>
        /// <returns></returns>
        public static async Task ComposeSms(string toPhoneNumber, string body)
        {
            var chatMessage = new Windows.ApplicationModel.Chat.ChatMessage();

            chatMessage.Body = body;
            chatMessage.Recipients.Add(toPhoneNumber);
            await ChatMessageManager.ShowComposeSmsMessageAsync(chatMessage);
        }
        private async void ProcessEContactClick(EContactItem selectedItem)
        {
            string content = string.Format("Call or message {0}?\nPress back to cancel.", selectedItem.Name);
            string title = "Information";

            string[] cmdString = new string[] { "call", "message" };
            MessageDialog md = new MessageDialog(content, title);
            md.Commands.Add(new UICommand(cmdString[0]));
            md.Commands.Add(new UICommand(cmdString[1]));

            IUICommand result = await md.ShowAsync();
            if (result == null) return;

            string resultString = result.Label;
            if (resultString == cmdString[0])
            {
                // Process call
                Windows.ApplicationModel.Calls.PhoneCallManager.ShowPhoneCallUI(selectedItem.Contact, selectedItem.Name);
            }
            else if (resultString == cmdString[1])
            {
                // Process message
                Windows.ApplicationModel.Chat.ChatMessage chatMsg = new Windows.ApplicationModel.Chat.ChatMessage();
                chatMsg.Recipients.Add(selectedItem.Contact);
                chatMsg.Body = "";
                await ChatMessageManager.ShowComposeSmsMessageAsync(chatMsg);
            }
        }