Cyrillic in tile notification?

Question

Windows

I had a problem when sending a tile notification with Cyrillic in the content. Everything works fine for Latin characters (for example, if you send text in transliteration). But if you send

"<wp:WideBackContent>" + XmlEncode("пример текста") + "</wp:WideBackContent>"

the message does not reach the device. If anyone has encountered a problem or can help in solving this problem, please contact me. Thank you.
Here is an example code:

protected void ButtonSendTile_Click(object sender, EventArgs e)

        {
            try
            {
                // Get the Uri that the Microsoft Push Notification Service returns to the Push Client when creating a notification channel.
                // Normally, a web service would listen for Uri's coming from the web client and maintain a list of Uri's to send
                // notifications out to.
                string subscriptionUri = TextBoxUri.Text.ToString();

                HttpWebRequest sendNotificationRequest = (HttpWebRequest)WebRequest.Create(subscriptionUri);

                // We will create a HTTPWebRequest that posts the tile notification to the Microsoft Push Notification Service.
                // HTTP POST is the only allowed method to send the notification.
                sendNotificationRequest.Method = "POST";

                // The optional custom header X-MessageID uniquely identifies a notification message. 
                // If it is present, the // same value is returned in the notification response. It must be a string that contains a UUID.
                // sendNotificationRequest.Headers.Add("X-MessageID", "<UUID>");

                // Create the tile message.
                string tileMessage = "<?xml version=\"1.0\" encoding=\"utf-8\"?>" +
                "<wp:Notification xmlns:wp=\"WPNotification\">" +
                    "<wp:Tile>" +
                     // "<wp:BackgroundImage>" + TextBoxBackgroundImage.Text + "</wp:BackgroundImage>" +
                     // "<wp:WideBackgroundImage>" + TextBoxBackgroundImage.Text + "</wp:WideBackgroundImage>" +
                      "<wp:Count>" + TextBoxCount.Text + "</wp:Count>" +
                      "<wp:Title>" + TextBoxTitle.Text + "</wp:Title>" +
                      //"<wp:BackBackgroundImage>" + TextBoxBackBackgroundImage.Text + "</wp:BackBackgroundImage>" +
                      "<wp:BackTitle>" + TextBoxBackTitle.Text + "</wp:BackTitle>" +
                      "<wp:WideBackContent>" + XmlEncode(TextBoxBackTitle.Text) + " wide" + "</wp:WideBackContent>" +
                      "<wp:BackContent>" + XmlEncode(TextBoxBackContent.Text) + "</wp:BackContent>" +
                   "</wp:Tile> " +
                "</wp:Notification>";

                // Sets the notification payload to send.
                byte[] notificationMessage = Encoding.Default.GetBytes(tileMessage);

                // Sets the web request content length.
                sendNotificationRequest.ContentLength = notificationMessage.Length;
                sendNotificationRequest.ContentType = "text/xml";
                sendNotificationRequest.Headers.Add("X-WindowsPhone-Target", "token");
                sendNotificationRequest.Headers.Add("X-NotificationClass", "1");


                using (Stream requestStream = sendNotificationRequest.GetRequestStream())
                {
                    requestStream.Write(notificationMessage, 0, notificationMessage.Length);
                }

                // Send the notification and get the response.
                HttpWebResponse response = (HttpWebResponse)sendNotificationRequest.GetResponse();
                string notificationStatus = response.Headers["X-NotificationStatus"];
                string notificationChannelStatus = response.Headers["X-SubscriptionStatus"];
                string deviceConnectionStatus = response.Headers["X-DeviceConnectionStatus"];

                // Display the response from the Microsoft Push Notification Service.  
                // Normally, error handling code would be here.  In the real world, because data connections are not always available,
                // notifications may need to be throttled back if the device cannot be reached.
                TextBoxResponse.Text = notificationStatus + " | " + deviceConnectionStatus + " | " + notificationChannelStatus;
            }
            catch (Exception ex)
            {
                TextBoxResponse.Text = "Exception caught sending update: " + ex.ToString();
            }

        }

        protected string XmlEncode(string text)
        {
            string a = System.Security.SecurityElement.Escape(text);
            return a;
        }
    }

Answer 1

Solved the problem.