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Timer to track websocket sharp messages in c#

I am using a websocket sharp dll in my windows application to get messages from a GDAX server. Everything is working fine so far - the messages are coming and i am processing them. The point where I am stuck is when the messages stops coming. At least I don't find anything in the WebSocket.OnMessage Event(https://github.com/sta/websocket-sharp) that can help me in tracking when the messages are stopped (I tried emitonping also)
Now the messages I received have a message type 'Heartbeat' which is sent every second. I want to add a separate timer control to check if the heartbeat messages are coming every second or not and if it stops coming then I will need to reconnect the server again. But since nothing happens when the messages stops coming how do i track it, where should I put the timer code to check when heartbeat messages stops coming?
I hope I could explain the situation wherein I am struck. If someone is eager to help me and needs more inputs please let me know.
Update
private void _3_Load(object sender, EventArgs e)
{
ConnectAndGetWebsocketFeedMessages();
}
public delegate void WSOpen(string text);
public delegate void WSMessage(string message);
public delegate void WSError(string text);
public delegate void WSClose(string text);
private static string _endPoint = "wss://ws-feed.gdax.com";
WebSocket ws = new WebSocket(_endPoint);
private bool IsConnected { get; set; }
private string ProductId { get; set; }
string productId = "LTC-EUR";
ConcurrentQueue<string> concurrentQueue = new ConcurrentQueue<string>();
public void SetWebSocketSharpEvents()
{
ws.Log.Level = LogLevel.Trace;
ws.OnOpen += (sender, e) =>
{
IsConnected = true;
OnWSOpen("Connection Status :: Connected *********");
};
ws.EmitOnPing = true;
ws.OnMessage += (sender, e) =>
{
if (e.IsPing)
{
OnWSMessage("ping received");
}
else
{
OnWSMessage(e.Data);
}
};
ws.OnError += (sender, e) =>
{
IsConnected = false;
OnWSError(e.Message); //An exception has occurred during an OnMessage event. An error has occurred in closing the connection.
if (ws.IsAlive)
ws.Close();
};
ws.OnClose += (sender, e) =>
{
IsConnected = false;
OnWSClose("Close");
};
ws.ConnectAsync();
}
private void ConnectAndGetWebsocketFeedMessages()
{
SetWebSocketSharpEvents();
}
private void SubscribeProduct(string sProductID)
{
if (IsConnected)
{
ProductId = sProductID;
string data = "{\"type\": \"subscribe\", \"product_ids\": [\"" + sProductID + "\"]}";
ws.Send(data);
ws.Send("{\"type\": \"heartbeat\", \"on\": true}");
}
}
void OnWSOpen(string text)
{
SubscribeProduct(productId);
timer1.Interval = 1000;
timer1.Tick += timer1_Tick;
timer1.Start();
}
DateTime lastHeartbeatTime = DateTime.MinValue;
bool isTimerStart = false;
void OnWSMessage(string message)
{
concurrentQueue.Enqueue(message);
SaveHeartbeatMessageTime(message);
ProcessMessage(message);
}
private void SaveHeartbeatMessageTime(string jsonString)
{
var jToken = JToken.Parse(jsonString);
var typeToken = jToken["type"];
var type = typeToken.ToString();
if (type == "heartbeat")
{
lastHeartbeatTime = DateTime.Now;
this.Invoke(new MethodInvoker(delegate()
{
lbllastheartbeat.Text = lastHeartbeatTime.ToLongTimeString();
}));
}
}
private void ProcessMessage(string message) { }
void OnWSError(string text) { }
void OnWSClose(string text) { }
bool isMessagesReceived = false;
private void timer1_Tick(object sender, EventArgs e) // it stops working as soon as lbllastheartbeat gets some value
{
DateTime currentTime = DateTime.Now;
TimeSpan duration = currentTime.Subtract(lastHeartbeatTime);
this.Invoke(new MethodInvoker(delegate()
{
lblNow.Text = currentTime.ToLongTimeString();
}));
if (Int16.Parse(duration.ToString("ss")) > 1)
{
// reconnect here
}
}
Edit
I am using windows form timer control and it keeps on calling timer1_Tick method and does not call OnWSMessage method. How do I ensure that both run parallel and if any message is missed or the message stops coming then it reconnects?
Edit2
The solutions provided below suggests to add the timer functionality in onMessage event but what will happen if I do not receive messages? If the messages are not received then the code does not do anything. I have taken a global variable and whenever a message comes it adds the time in that variable. Now I want to run a separate timer control which will check whether there is anything in that variable and if its value i.e difference of seconds is more than 1 then do something else keep on checking.
Is there anyone who can look into this and advise please.
Update2: I still want to do this with windows.timer control and not threading.timer. I have taken two labels in my windows app, lbllastheartbeat (to show the time when heartbeat message is received) and lblNow (to show the current time when timer is called).
Requirement - My timer will check if any heartbeat message is missed and that is done through the 'lastHeartbeatTime' variable which stores the time when the heartbeat message is received.
I would appreciate if anyone can review my code and suggest what or where I am doing wrong.

The answer has already been given - you need to start timer which will fire after your timeout period when you receive message, and reset that timer every time you receive message. But it seems you want code example, so here it is (with comments):
System.Threading.Timer _timeoutTimer;
private readonly object _timeoutTimerLock = new object();
private void ResetTimeoutTimer() {
// if you are sure you will never access this from multiple threads at the same time - remove lock
lock (_timeoutTimerLock) {
// initialize or reset the timer to fire once, after 2 seconds
if (_timeoutTimer == null)
_timeoutTimer = new System.Threading.Timer(ReconnectAfterTimeout, null, TimeSpan.FromSeconds(2), Timeout.InfiniteTimeSpan);
else
_timeoutTimer.Change(TimeSpan.FromSeconds(2), Timeout.InfiniteTimeSpan);
}
}
private void StopTimeoutTimer() {
// if you are sure you will never access this from multiple threads at the same time - remove lock
lock (_timeoutTimerLock) {
if (_timeoutTimer != null)
_timeoutTimer.Change(Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
}
}
private void ReconnectAfterTimeout(object state) {
// reconnect here
}
public void SetWebSocketSharpEvents() {
ws.Log.Level = LogLevel.Trace;
ws.OnOpen += (sender, e) => {
// start timer here so that if you don't get first message after 2 seconds - reconnect
ResetTimeoutTimer();
IsConnected = true;
OnWSOpen("Connection Status :: Connected *********");
};
ws.EmitOnPing = true;
ws.OnMessage += (sender, e) => {
// and here
ResetTimeoutTimer();
if (e.IsPing) {
OnWSMessage("ping received");
}
else {
OnWSMessage(e.Data);
}
};
ws.OnError += (sender, e) => {
// stop it here
StopTimeoutTimer();
IsConnected = false;
OnWSError(e.Message); //An exception has occurred during an OnMessage event. An error has occurred in closing the connection.
if (ws.IsAlive)
ws.Close();
};
ws.OnClose += (sender, e) => {
// and here
StopTimeoutTimer();
IsConnected = false;
OnWSClose("Close");
};
ws.ConnectAsync();
}

from your question what i understand is , your message is sending after every seconds , but the problem is only when it stop you want to know and run it again, if it like that , you just apply timer and check for every seconds if the message not sent after a second or more (check sentMessage() Method set a boolean if message sent it should give true otherwise false) , than give the command to reconnect the server again .

Why value does not fall within the expected range when setting Value Changed for Gatt Characteristic

I would like to keep on reading characteristic/set value changed event handlers for characteristics from my BLE 4.0 device, by using the ValueChanged callback in Universal Windows Platform C# in Visual Studio 2017.
I followed some tutorial from these sites: Damian Blog's Windows Universal with BLE, Bluetooth Gatt's Git Hub, Bluetooth Generic Attribute Profile - Heart Rate Service and Dr. Jukka's mobile Blog on BLE. All of them are using ValueChanged and I have tried to follow what they did.
Unfortunately, instead of ValueChanged being triggered, I receive the following error when using the ValueChanged callback.
System.ArgumentException: 'Value does not fall within the expected range.'
This line of code is producing the error:
characteristic.ValueChanged += Oncharacteristic_ValueChanged;
Here is more details of my source code:
NOTE: I am using COM 7 for my dongler and my program could discover the BLE's device name, and could discover the Uuid of the services and characteristics.
public List<string> serviceList = new List<string>();
public List<string> characteristicList = new List<string>();
public BluetoothLEDevice myDevice { get; set; }
public MainPage()
{
this.InitializeComponent();
}
private async void Page_Loaded(object sender, RoutedEventArgs e)
{
// Find the com port
string selector = SerialDevice.GetDeviceSelector("COM7");
DeviceInformationCollection devices = await DeviceInformation.FindAllAsync(selector);
if (devices.Count > 0)
{
var dialog = new MessageDialog("Com Device found");
await dialog.ShowAsync();
DeviceInformation deviceInfo = devices[0];
SerialDevice serialDevice = await SerialDevice.FromIdAsync(deviceInfo.Id);
serialDevice.BaudRate = 9600;
serialDevice.DataBits = 8;
serialDevice.StopBits = SerialStopBitCount.One;
serialDevice.Parity = SerialParity.None;
}
else
{
MessageDialog popup = new MessageDialog("Sorry, no device found.");
await popup.ShowAsync();
}
// After com port is found, search for device
foreach (DeviceInformation di in await DeviceInformation.FindAllAsync(BluetoothLEDevice.GetDeviceSelector()))
{
BluetoothLEDevice bleDevice = await BluetoothLEDevice.FromIdAsync(di.Id);
// Display BLE device name
var dialogBleDeviceName = new MessageDialog("BLE Device Name " + bleDevice.Name);
await dialogBleDeviceName.ShowAsync();
myDevice = bleDevice;
}
// Check device connection
myDevice.ConnectionStatusChanged += OnConnectionStatusChanged;
foreach (var service in myDevice.GattServices)
{
serviceList.Add(service.Uuid.ToString());
// Verify if service is discovered by displaying a popup
MessageDialog serviceUuidPopUp = new MessageDialog("Adding Service Uuid to list " + service.Uuid.ToString() );
await serviceUuidPopUp.ShowAsync();
foreach (var characteristic in service.GetAllCharacteristics())
{
var characteristicUuid = characteristic.Uuid.ToString().ToLowerInvariant();
characteristicList.Add(characteristicUuid);
// Verify if characteristic is discovered by displaying a popup
MessageDialog charUuidPopUp = new MessageDialog("Adding characteristic Uuid to list " + characteristicUuid);
await charUuidPopUp.ShowAsync();
// set value changed event handlers for characteristics
characteristic.ValueChanged += Oncharacteristic_ValueChanged;
}
}
}
private void OnConnectionStatusChanged(BluetoothLEDevice sender, object args)
{
if (sender.ConnectionStatus == BluetoothConnectionStatus.Connected)
{
System.Diagnostics.Debug.WriteLine("Connected");
}
else
{
System.Diagnostics.Debug.WriteLine("Disconnected");
}
}
private void Oncharacteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args)
{
byte[] data = new byte[args.CharacteristicValue.Length];
DataReader.FromBuffer(
args.CharacteristicValue).ReadBytes(data);
string text = Encoding.UTF8.GetString(data, 0, data.Length);
}
UPDATE 1
I tried to check Characteristic Properties before set value changed event handlers for my characteristics by following the answer given by rudi belt on SO.
if (characteristic.CharacteristicProperties == (GattCharacteristicProperties.Read | GattCharacteristicProperties.Notify))
{
characteristic.ValueChanged += Oncharacteristic_ValueChanged;
}
Unfortunately, this IF statement is not executed.
UPDATE 2
I have tried to remove ALL the codes inside Oncharacteristic_ValueChanged method. But it still gives me the same error
System.ArgumentException: 'Value does not fall within the expected range.'
I have been spending a lot of time trying to solve this problem. I will be very happy if anyone can help me on this. Thank you!

Reading your efforts in the former question I can provide a working example, but first some explanation.
myDevice.ConnectionStatusChanged is not needed, it is only used to notice a connection is lost or connected. You have to connect to your device first and handle things in the connection method.
After you have succeeded in connecting you have to get the service that contains the characteristic you want to use for read, write, notify or indicate.
When you have selected the service You can get the characteristics of that service.
Select the characteristic by Uuid, or in my example with CharacteristicProperties.HasFlag.
This flag in my example is Notify.
In the code comments you find extra info.
using System;
using System.Diagnostics;
using System.Threading.Tasks;
using Windows.Devices.Bluetooth;
using Windows.Devices.Bluetooth.GenericAttributeProfile;
using Windows.Devices.Enumeration;
using Windows.UI.Popups;
using Windows.UI.Xaml.Controls;
namespace App1
{
public sealed partial class MainPage : Page
{
GattDeviceServicesResult serviceResult = null;
private BluetoothLEDevice myDevice;
private GattCharacteristic selectedCharacteristic;
public MainPage()
{
this.InitializeComponent();
ConnectDevice();
}
private async void ConnectDevice()
{
//This works only if your device is already paired!
foreach (DeviceInformation di in await DeviceInformation.FindAllAsync(BluetoothLEDevice.GetDeviceSelector()))
{
BluetoothLEDevice bleDevice = await BluetoothLEDevice.FromIdAsync(di.Id);
// Display BLE device name
var dialogBleDeviceName = new MessageDialog("BLE Device Name " + bleDevice.Name);
await dialogBleDeviceName.ShowAsync();
myDevice = bleDevice;
}
if (myDevice != null)
{
int servicesCount = 3;//Fill in the amount of services from your device!!!!!
int tryCount = 0;
bool connected = false;
while (!connected)//This is to make sure all services are found.
{
tryCount++;
serviceResult = await myDevice.GetGattServicesAsync();
if (serviceResult.Status == GattCommunicationStatus.Success && serviceResult.Services.Count >= servicesCount)
{
connected = true;
Debug.WriteLine("Connected in " + tryCount + " tries");
}
if (tryCount > 5)//make this larger if faild
{
Debug.WriteLine("Failed to connect to device ");
return;
}
}
if (connected)
{
for (int i = 0; i < serviceResult.Services.Count; i++)
{
var service = serviceResult.Services[i];
//This must be the service that contains the Gatt-Characteristic you want to read from or write to !!!!!!!.
string myServiceUuid = "0000ffe0-0000-1000-8000-00805f9b34fb";
if (service.Uuid.ToString() == myServiceUuid)
{
Get_Characteriisics(service);
break;
}
}
}
}
}
private async void Get_Characteriisics(GattDeviceService myService)
{
var CharResult = await myService.GetCharacteristicsAsync();
if (CharResult.Status == GattCommunicationStatus.Success)
{
foreach (GattCharacteristic c in CharResult.Characteristics)
{
if (c.CharacteristicProperties.HasFlag(GattCharacteristicProperties.Notify))
{
selectedCharacteristic = c;
break;
}
}
try
{
// Write the ClientCharacteristicConfigurationDescriptor in order for server to send notifications.
var result = await selectedCharacteristic.WriteClientCharacteristicConfigurationDescriptorAsync(
GattClientCharacteristicConfigurationDescriptorValue.Notify);
if (result == GattCommunicationStatus.Success)
{
var dialogNotifications = new MessageDialog("Successfully registered for notifications");
await dialogNotifications.ShowAsync();
selectedCharacteristic.ValueChanged += SelectedCharacteristic_ValueChanged;
}
else
{
var dialogNotifications = new MessageDialog($"Error registering for notifications: {result}");
await dialogNotifications.ShowAsync();
}
}
catch (Exception ex)
{
// This usually happens when not all characteristics are found
// or selected characteristic has no Notify.
var dialogNotifications = new MessageDialog(ex.Message);
await dialogNotifications.ShowAsync();
await Task.Delay(100);
Get_Characteriisics(myService); //try again
//!!! Add a max try counter to prevent infinite loop!!!!!!!
}
}
else
{
var dialogNotifications = new MessageDialog("Restricted service. Can't read characteristics");
await dialogNotifications.ShowAsync();
}
}
private void SelectedCharacteristic_ValueChanged(GattCharacteristic sender, GattValueChangedEventArgs args)
{
}
}
}
If you have problems with this code feel free to ask in comments.

Azure: How to Delete "DeadLettered" Messages from Service Bus queue

I would like to delete the Dead Lettered messages from the service bus queue. In particular, this value is called DeadLetterMessageCount and you can find out this by right-clicking the "Properties" of the SB queue in the Server Explorer of your project (in case of using a SB queue).
The reason I would like to do this is because I've set up an Autoscale of the cloud service. So, when the SB queue is quite big, it adds some more cores in order to proceed the messages faster (it enables more worker roles). I realized that when you set up the scaling depending on the number of messages in the queue, it counts the DeadLettered messages as well (messages that cannot be consumed).
So that's a waste of money, as more instances are enabled that are not needed.
Any queries, please let me know.
Thanks for your help

You read and delete messages from dead letter queue the same way you read from normal queues or subscriptions.
You can use this method to get the path of the queue: QueueClient.FormatDeadLetterPath(queuePath).
Also see this previous answer: How do I delete a DeadLetter message on an Azure Service Bus Topic

This is a code to delete a Dead-Letter messages from Queues.
public async void DeleteMessagesFromQueueAsync()
{
bool isDeadLetter=true;
long SequenceNumber = 12;
string queuePath='queue name';
string connectionString='connection string of ASB Namespace';
BrokeredMessage _srcMessage = null;
DeleteMessageResponse _msgDeletionStatus = new DeleteMessageResponse();
MessageReceiver fromQueueClient = null;
try
{
MessagingFactory factory = MessagingFactory.CreateFromConnectionString(connectionString);
string _fromEntityPath = !isDeadLetter ? queuePath : QueueClient.FormatDeadLetterPath(queuePath);
fromQueueClient = await factory.CreateMessageReceiverAsync(_fromEntityPath, ReceiveMode.PeekLock);
BrokeredMessage _message = await fromQueueClient.ReceiveAsync(SequenceNumber);
if (_message != null)
_srcMessage= _message;
if (_srcMessage != null )
{
await _srcMessage.CompleteAsync();
}
}
catch (Exception ex)
{
}
finally
{
if (fromQueueClient != null)
await fromQueueClient.CloseAsync();
}
}

You can use 'ReceiveAndDelete' mode and 'ReceiveBatchAsync' to delete quickly from DeadLetterQueue
private async void button1_Click(object sender, EventArgs e)
{
try
{
var DLQPath = "/$DeadLetterQueue"; ///**** Important - Pointing to DLQ'
var topicName = "message";
var sub = "message-subscription";
int batchSize = 100;
runProcess = true;
_subscriptionClient = SubscriptionClient.CreateFromConnectionString(connectionSt, topicName, sub + DLQPath, ReceiveMode.ReceiveAndDelete);
int cnt = 0;
do
{
var messages = await _subscriptionClient.ReceiveBatchAsync(batchSize);
var msgCount = messages.Count();
if (msgCount == 0)
{
break;
}
cnt += msgCount;
labelCount.Text = cnt.ToString();
}
while (runProcess);
_subscriptionClient.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.GetBaseException().Message);
return;
}
}

How to prevent WMI quotas from overflowing?

I am using a C# application to monitor the processes launched from a particular folder, and I am using WMI for monitoring. My WMI query is like
SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process' AND TargetInstance.ExecutablePath LIKE '{0}%'
where I substitute the parameter with the path to the folder which I am intereseted. The WMI query is working fine and I am subscribing to the event notifications to do some additional processsing when a process from the particular folder comes up. The monitoring tool runs fine for hours after which I start getting a WMI QuotaViolation exception in my app. Once this happens I need to restart the Windows Management Instrumentation service to get the thing working.
I was initially using a
`SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process'`
query and then checking the processes folder in the event notification, the modification in the query was done hoping it would reduce the result set and therefore prevent the Quota Violation.
Is there any way to flush the WMI quotas periodically or any other method whereby I can prevent the QuotaViolation? What is the best way to handle a QuotaViolation scenario?
Edit:
This is my process watcher object :
public class ProcessWatcher : ManagementEventWatcher
{
private string folder = "";
// Process Events
public event ProcessEventHandler ProcessCreated; //notifies process creation
//add any more event notifications required here
// WMI WQL process query strings
static readonly string WMI_OPER_EVENT_QUERY = #"SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process'";
static readonly string WMI_OPER_EVENT_QUERY_WITH_PROC =
WMI_OPER_EVENT_QUERY + " and TargetInstance.Name = '{0}'";
public ProcessWatcher(string basepath)
{
folder = basepath;
Init(string.Empty);
}
public ProcessWatcher(string processName, string basepath)
{
folder = basepath;
Init(processName);
}
private void Init(string processName)
{
this.Query.QueryLanguage = "WQL";
if (string.IsNullOrEmpty(processName))
{
this.Query.QueryString = string.Format(WMI_OPER_EVENT_QUERY + #" AND TargetInstance.ExecutablePath LIKE '{0}%'", folder.Replace(#"\",#"\\")) ;
}
else
{
this.Query.QueryString =
string.Format(WMI_OPER_EVENT_QUERY_WITH_PROC, processName);
}
this.EventArrived += new EventArrivedEventHandler(watcher_EventArrived);
}
private void watcher_EventArrived(object sender, EventArrivedEventArgs e)
{
try
{
ManagementBaseObject mObj = e.NewEvent["TargetInstance"] as ManagementBaseObject;
if (mObj != null)
{
Win32_Process proc = new Win32_Process(mObj);
if (proc != null)
{
folder = folder.ToLower() ?? "";
string exepath = (string.IsNullOrEmpty(proc.ExecutablePath)) ? "" : proc.ExecutablePath.ToLower();
if (!string.IsNullOrEmpty(folder) && !string.IsNullOrEmpty(exepath) && exepath.Contains(folder))
{
if (ProcessCreated != null) ProcessCreated(proc);
}
}
proc.Dispose();
}
mObj.Dispose();
}
catch(Exception ex) { throw; }
finally
{
e.NewEvent.Dispose();
}
}
I create a ProcessWatcher object at app startup, in a viewmodel constructor like :
watch = new ProcessWatcher(BasePath);
watch.ProcessCreated += new ProcessEventHandler(procWatcher_ProcessCreated);
watch.Start();
The start call is where the QuotaViolation is raised if I try to start it a second time without restarting WMI.
At app exit, I am disposing off the ProcessWatcher object like :
watch.Stop();
watch.Dispose();
The Relevant Stack trace is :
Exception InnerException [System.Management.ManagementException: Quota violation
at System.Management.ManagementException.ThrowWithExtendedInfo(ManagementStatus errorCode)
at System.Management.ManagementEventWatcher.Start()
at App.ProcessTabViewModel1..ctor()

System.Management.ManagementException: Quota violation
Yes, that happens. I wrote a little test program, based on your snippet after adding the missing pieces:
static void Main(string[] args) {
for (int ix = 0; ix < 1000; ++ix) {
var obj = new ProcessWatcher("");
obj.ProcessCreated += obj_ProcessCreated;
obj.Start();
}
}
Kaboom! With the exact same stack trace as you quoted. It conked out at ix == 76. In other words, the WMI quota for this query is 75. Tested in Windows 8.1. Feels about right, this is a very expensive query, none too fast either.
You are going to have to do this fundamentally different, create only one query. One is enough, you probably got into trouble by doing this for many folders. Attack that differently, do your own filtering when you get the event. A rough example (I didn't quite get the filtering you want to do):
public class ProcessWatcher2 : IDisposable {
public delegate void ProcessCreateEvent(string name, string path);
public event ProcessCreateEvent ProcessCreated;
public ProcessWatcher2(string folder) {
this.folder = folder;
lock (locker) {
listeners.Add(this);
if (watcher == null) Initialize();
}
}
public void Dispose() {
lock (locker) {
listeners.Remove(this);
if (listeners.Count == 0) {
watcher.Stop();
watcher.Dispose();
watcher = null;
}
}
}
private static void Initialize() {
var query = new WqlEventQuery(#"SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process'");
watcher = new ManagementEventWatcher(query);
watcher.EventArrived += watcher_EventArrived;
watcher.Start();
}
private static void watcher_EventArrived(object sender, EventArrivedEventArgs e) {
using (var proc = (ManagementBaseObject)e.NewEvent["TargetInstance"]) {
string name = (string)proc.Properties["Name"].Value;
string path = (string)proc.Properties["ExecutablePath"].Value;
lock (locker) {
foreach (var listener in listeners) {
bool filtered = false;
// Todo: implement your filtering
//...
var handler = listener.ProcessCreated;
if (!filtered && handler != null) {
handler(name, path);
}
}
}
}
}
private static ManagementEventWatcher watcher;
private static List<ProcessWatcher2> listeners = new List<ProcessWatcher2>();
private static object locker = new object();
private string folder;
}

Receiving Notfication when app is running

In fear of asking a question that might have been asked before, but my search skills did not able me to find. Okay, so here goes.
I have Windows Phone 8 App, where I can receive TileUpdates and Notifications, when My app is not running in the foreground. This I did by following http://msdn.microsoft.com/en-us/library/windowsphone/develop/hh202940(v=vs.105).aspx
In that link I learned that for getting notifications when app is running I should simply attach an event for the reception case. This I did in my AcquirePushChannel() function, which looks as follows:
public static void AcquirePushChannel()
{
CurrentChannel = HttpNotificationChannel.Find("MyPushChannel");
if (CurrentChannel == null)
{
CurrentChannel = new HttpNotificationChannel("MyPushChannel");
CurrentChannel.Open();
if (!CurrentChannel.IsShellToastBound)
{
CurrentChannel.BindToShellTile();
}
CurrentChannel.BindToShellToast();
CurrentChannel.ShellToastNotificationReceived += new EventHandler<NotificationEventArgs>(Push_NotificationRecieved);
}
if (!CurrentChannel.IsShellTileBound)
{
CurrentChannel.BindToShellToast();
CurrentChannel.ShellToastNotificationReceived += new EventHandler<NotificationEventArgs>(Push_NotificationRecieved);
}
CurrentChannel.ChannelUriUpdated += new EventHandler<NotificationChannelUriEventArgs>(Push_NotificationChannelChanged);
}
I have implemented CurrentChannel.ChannelUriUpdated, for the case that channelUri changes and I execute some code to also changes my ChannelsTable in the Cloud.
My Push_NotificationRecieved looks like:
private static void Push_NotificationRecieved(object sender, NotificationEventArgs e)
{
StringBuilder message = new StringBuilder();
string relativeUri = string.Empty;
message.AppendFormat("Received Toast {0}:\n", DateTime.Now.ToShortTimeString());
// Parse out the information that was part of the message.
foreach (string key in e.Collection.Keys)
{
message.AppendFormat("{0}: {1}\n", key, e.Collection[key]);
if (string.Compare(
key,
"wp:Param",
System.Globalization.CultureInfo.InvariantCulture,
System.Globalization.CompareOptions.IgnoreCase) == 0)
{
relativeUri = e.Collection[key];
}
}
// Display a dialog of all the fields in the toast.
MessageBox.Show(message.ToString());
//Dispatcher.BeginInvoke((message) => MessageBox.Show(message.ToString()));
}
I cannot see why the notification is not registered. Since in my log in the cloud I receive that the Toast Notification was received?
Any Ideas? Furthermore can I display the toast from the code or something similar, as far as I have read it is not possible?
Extra
Have tried changing the functions to public but did not help with the problem.
Anybody have an Idea to why the event is not firing.

The answer you posted is almost correct. From the previous you have:
public static void AcquirePushChannel()
{
CurrentChannel = HttpNotificationChannel.Find("MyPushChannel");
if (CurrentChannel == null)
{
CurrentChannel = new HttpNotificationChannel("MyPushChannel");
CurrentChannel.Open();
if (!CurrentChannel.IsShellToastBound)
{
CurrentChannel.BindToShellTile();
}
CurrentChannel.BindToShellToast();
}
if (!CurrentChannel.IsShellTileBound)
{
CurrentChannel.BindToShellToast();
}
CurrentChannel.ChannelUriUpdated += new EventHandler<NotificationChannelUriEventArgs>(Push_NotificationChannelChanged);
CurrentChannel.ShellToastNotificationReceived += CurrentChannel_ShellToastNotificationReceived;
}
And to that you have to add:
private static void CurrentChannel_ShellToastNotificationReceived(object sender, NotificationEventArgs e)
{
StringBuilder message = new StringBuilder();
string relativeUri = string.Empty;
message.AppendFormat("Received Toast {0}:\n", DateTime.Now.ToShortTimeString());
// Parse out the information that was part of the message.
foreach (string key in e.Collection.Keys)
{
message.AppendFormat("{0}: {1}\n", key, e.Collection[key]);
if (string.Compare(
key,
"wp:Param",
System.Globalization.CultureInfo.InvariantCulture,
System.Globalization.CompareOptions.IgnoreCase) == 0)
{
relativeUri = e.Collection[key];
}
}
// Display a dialog of all the fields in the toast.
MessageBox.Show(message.ToString());
}
So all you send is inside the e.collection. So you can from the server send all kind of parameters.

Of course just after I set a bounty to run I got it working. So here is the updated code.
public static void AcquirePushChannel()
{
CurrentChannel = HttpNotificationChannel.Find("MyPushChannel");
if (CurrentChannel == null)
{
CurrentChannel = new HttpNotificationChannel("MyPushChannel");
CurrentChannel.Open();
if (!CurrentChannel.IsShellToastBound)
{
CurrentChannel.BindToShellTile();
}
CurrentChannel.BindToShellToast();
}
if (!CurrentChannel.IsShellTileBound)
{
CurrentChannel.BindToShellToast();
}
CurrentChannel.ChannelUriUpdated += new EventHandler<NotificationChannelUriEventArgs>(Push_NotificationChannelChanged);
CurrentChannel.ShellToastNotificationReceived += CurrentChannel_ShellToastNotificationReceived;
}
Okay so the reason for this, is that you need to set the events on every startup. Then you will get the wished properties. Then you have to create your own code for getting what you want :)