Windows Service installed but not working???

  • Thread starter Thread starter acool
  • Start date Start date
A

acool

I managed to get my VB.NET service installed. Now I can't get it to do
anything. Tell me how do you debug smething like this if you have to
manually install the assembly to run it? the same code works just fine in a
VB form but when I initiallize with the WS OnStart event I get nothing. Any
help is greatly appreciated.



TB
 
Are you doing too much work in the OnStart method?

Have you tried debugging your service:
http://msdn.microsoft.com/library/d.../vsdebug/html/vxtskdebugginwindowsservice.asp

Specifically:
http://msdn.microsoft.com/library/d...on/html/vbtskdebuggingserviceapplications.asp

Normally what I do is include a healthy amount of event log messages (via
theServiceBase.EventLog property ) especially in any asynchronous events
that may be raised within the service. Plus I will include Debug.Write &
Trace.Write in strategic locations.

Something like:

Public Class MyService
Inherits System.ServiceProcess.ServiceBase

Private WithEvents Timer1 As System.Timers.Timer

Public Sub New()
MyBase.New()

' This call is required by the Component Designer.
InitializeComponent()

' Add any initialization after the InitializeComponent() call

AddHandler AppDomain.CurrentDomain.UnhandledException, _
AddressOf AppDomain_UnhandledException
End Sub

Protected Overrides Sub OnStart(ByVal args() As String)
' Add code here to start your service. This method should set things
' in motion so your service can do its work.
Timer1.Start()
End Sub

Protected Overrides Sub OnStop()
' Add code here to perform any tear-down necessary to stop your
service.
Timer1.Stop()
End Sub

Private Sub Timer1_Elapsed(ByVal sender As System.Object, ByVal e As
System.Timers.ElapsedEventArgs) Handles Timer1.Elapsed
Try
EventLog.WriteEntry("Timer elapsed handler started",
EventLogEntryType.Information)

' Do work here

EventLog.WriteEntry("Timer elapsed handler finished",
EventLogEntryType.Information)
Catch ex As Exception
EventLog.WriteEntry(ex.ToString(), EventLogEntryType.Error)
End Try
End Sub

Private Sub AppDomain_UnhandledException(ByVal sender As Object, _
ByVal e As UnhandledExceptionEventArgs)
EventLog.WriteEntry(e.ExceptionObject.ToString(),
EventLogEntryType.Error)
End Sub


End Class

Note EventLog is inherited from ServiceBase and will be the normal event log
for your service, you can override ServiceBase.EventLog if you want to use a
different Event log.

I configure Debug & Trace to go to a log file.

In your app.config of your Windows Service project:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<system.diagnostics>
<trace autoflush="true" indentsize="4">
<listeners>
<add name="myListener" type="System.Diagnostics.TextWriterTraceListener"
initializeData="MyService.log" />
</listeners>
</trace>
</system.diagnostics>
</configuration>


Note the UnhandledException event is not working as I expected in the above,
so I put the Elapsed event in its own Try/Catch.

Hope this helps
Jay
 
acool said:
I managed to get my VB.NET service installed. Now I can't get it to do
anything. Tell me how do you debug smething like this if you have to
manually install the assembly to run it?
Click to expand...

Start the Service, then atach to the running Process.
the same code works just fine in a VB form but when I initiallize with
the WS OnStart event I get nothing.
Click to expand...

Is your Service running beyond the onStart Event? Timer? Closed
loop woith a Sleep() call in it?
Remember that you have to have an application "thread" running for
the Service to /continue/ to work and you get one of those for free
in a Form.

HTH,
Phill W.
 
I think I am missing soething here is my code:

Imports System.ServiceProcess
Imports System.IO
Imports System.Diagnostics

Protected Overrides Sub OnStart(ByVal args() As String)
' Create a new FileSystemWatcher and set its properties.

Dim watcher As New FileSystemWatcher
watcher.Path = "C:\Temp"
watcher.Filter = "*.xls"

' Add event handlers.
AddHandler watcher.Changed, AddressOf OnChanged
AddHandler watcher.Created, AddressOf OnCreated
AddHandler watcher.Deleted, AddressOf OnChanged
AddHandler watcher.Renamed, AddressOf OnRenamed

' Begin watching.
watcher.EnableRaisingEvents = True

End Sub

' Define the event handlers.
Private Shared Sub OnChanged(ByVal source As Object, ByVal e As
FileSystemEventArgs)
' Specify what is done when a file is changed, created, or deleted.
End Sub

Private Shared Sub OnRenamed(ByVal source As Object, ByVal e As
RenamedEventArgs)
' Specify what is done when a file is renamed.
End Sub

Private Sub OnCreated(ByVal source As Object, ByVal e As
FileSystemEventArgs)
' Specify what is done when a file is created.
File.Create("C:\Temp\OnCreated.txt")
End Sub

So basically when I drop an excel file in my temp folder I want the
OnCreated event to do something. This works fine in a form but not in my
service. I knw I am missing something I just don't know what.
 
Your code by the gives me the following error:


Service cannot be started. System.NullReferenceException: Object reference
not set to an instance of an object.
at WindowsService1.Service1.OnStart(String[] args) in
C:\Dev\WindowsService1\Service1.vb:line 79
at System.ServiceProcess.ServiceBase.ServiceQueuedMainCallback(Object
state)


It bombs on the
Timer1.Start()

method
 
acool,
You do realize that my code is no where near a complete sample, it is a
partial sample to give you a feel for where to insert EventLog.WriteEntry
statements, to help identify problems.

Hope this helps
Jay

acool said:
Your code by the gives me the following error:


Service cannot be started. System.NullReferenceException: Object reference
not set to an instance of an object.
at WindowsService1.Service1.OnStart(String[] args) in
C:\Dev\WindowsService1\Service1.vb:line 79
at System.ServiceProcess.ServiceBase.ServiceQueuedMainCallback(Object
state)


It bombs on the
Timer1.Start()

method




Jay B. Harlow said:
Are you doing too much work in the OnStart method?

Have you tried debugging your service:
Click to expand...
http://msdn.microsoft.com/library/d...on/html/vbtskdebuggingserviceapplications.asp
Normally what I do is include a healthy amount of event log messages (via
theServiceBase.EventLog property ) especially in any asynchronous events
that may be raised within the service. Plus I will include Debug.Write &
Trace.Write in strategic locations.

Something like:

Public Class MyService
Inherits System.ServiceProcess.ServiceBase

Private WithEvents Timer1 As System.Timers.Timer

Public Sub New()
MyBase.New()

' This call is required by the Component Designer.
InitializeComponent()

' Add any initialization after the InitializeComponent() call

AddHandler AppDomain.CurrentDomain.UnhandledException, _
AddressOf AppDomain_UnhandledException
End Sub

Protected Overrides Sub OnStart(ByVal args() As String)
' Add code here to start your service. This method should set things
' in motion so your service can do its work.
Timer1.Start()
End Sub

Protected Overrides Sub OnStop()
' Add code here to perform any tear-down necessary to stop your
service.
Timer1.Stop()
End Sub

Private Sub Timer1_Elapsed(ByVal sender As System.Object, ByVal e As
System.Timers.ElapsedEventArgs) Handles Timer1.Elapsed
Try
EventLog.WriteEntry("Timer elapsed handler started",
EventLogEntryType.Information)

' Do work here

EventLog.WriteEntry("Timer elapsed handler finished",
EventLogEntryType.Information)
Catch ex As Exception
EventLog.WriteEntry(ex.ToString(), EventLogEntryType.Error)
End Try
End Sub

Private Sub AppDomain_UnhandledException(ByVal sender As Object, _
ByVal e As UnhandledExceptionEventArgs)
EventLog.WriteEntry(e.ExceptionObject.ToString(),
EventLogEntryType.Error)
End Sub


End Class

Note EventLog is inherited from ServiceBase and will be the normal event log
for your service, you can override ServiceBase.EventLog if you want to
Click to expand...
use
a
different Event log.

I configure Debug & Trace to go to a log file.

In your app.config of your Windows Service project:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<system.diagnostics>
<trace autoflush="true" indentsize="4">
<listeners>
<add name="myListener" type="System.Diagnostics.TextWriterTraceListener"
initializeData="MyService.log" />
</listeners>
</trace>
</system.diagnostics>
</configuration>


Note the UnhandledException event is not working as I expected in the above,
so I put the Elapsed event in its own Try/Catch.

Hope this helps
Jay


in nothing.
Any
Click to expand...
Click to expand...
 
acool,
Did you try putting EventLog.WriteEntry entries in your OnChanged,
OnCreated, OnRenamed methods to see when or if they are being called?
' Define the event handlers.
Private Shared Sub OnChanged(ByVal source As Object, ByVal e As
FileSystemEventArgs)
Click to expand...

EventLog.WriteEntry("OnChanged started", _
EventLogEntryType.Information)
' Specify what is done when a file is changed, created, or
Click to expand...
deleted.

EventLog.WriteEntry("OnChanged ended", _
EventLogEntryType.Information)
End Sub
Click to expand...


Are you calling MyBase.OnStart? Did you try putting extra
EventLog.WriteEntry's in your OnStart to make sure it finishes?

Did you use Event Viewer in Control Panel - Admistrative Tools to see your
events that are written above?

Alternatively did you try Trace.Write or Debug.Write and the app.config to
write to a log file to see what is happening?

Did you attempt to debug your app (start it, put break points in OnChanged,
OnCreated, OnRenamed methods) to see what happens?

Hope this helps
Jay
 
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