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POThreads / Timers Troubles While Creating System Service Under VB.NET 4
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copied!<p>I thought that creating a simple system service under VB .NET would be a piece of cake. Boy, was I wrong. First, I find general postings through Google that say you should use the Windows.Forms.Timer. Then, I found conflicting information that says you have to derive the timer from a timer class through code to make it work. Then, people are reporting all sorts of trouble using the various types of threads available. I can't debug threads using the VS 2010 Just-in-Time debugger for obvious reasons (although, I don't know if there is an alternate method to doing this). Wow, how confusing all this is when there is no definitive guide...</p> <p>My project is an application launcher (similar to cron) that will fire off periodically within a certain amount of seconds. I am trying to use the Process.Start() method. I have a Beep() function as the first instruction, and the Process.Start, along with a Process.WaitForExit method to make it block as the last instruction. I had my code doing this through timers, but now I am starting to use threads. No difference in execution. The over-ridden OnStart method does kick off (as I am certain through debugging), but nothing ever happens when starting the service in production, as if it were ignoring all my code. Putting loops and logic in the OnStart method yields a process that won't start. I know it is a threading issue, but I also know it must be mandatory to use threads. I am now dumbfounded as to how to make this work. I am curious to know the solution.</p> <p>In addition to the service class, I have a ServiceInstaller and ProcessInstaller implemented that I copied verbatim from MSDN.</p> <p>Here is some of the code I am trying to work with. Note that this simply reflects the current state of my code in trying to implement the logic within a thread instead of a timer (which to me would be optimal):</p> <pre><code> Dim config As String Dim configValues(2) As String Dim objReader As System.IO.StreamReader Dim interval As Integer Dim launchProcess As Process While True Beep() ' This sub runs every time the elapsed milli-seconds of the timer pass ' Sp add your code here. config = "30 c:\WiFiDropOutFix\start.vbs" Try objReader = New System.IO.StreamReader("C:\WiFiDropOutFix\config.txt") config = objReader.ReadToEnd objReader.Close() Catch ex As Exception End Try configValues = config.Split(New Char() {" "c}) interval = Convert.ToInt32(configValues(0)) If Not interval > 0 And Not interval < 61 Then interval = 10 End If launchProcess = Process.Start(configValues(1)) launchProcess.WaitForExit() Thread.Sleep(interval * 1000) End While End Sub </code></pre> <p>Here is my OnStart Code by Request:</p> <pre><code>Protected Overrides Sub OnStart(ByVal args() As String) appLaunchLogicThread = New Thread(AddressOf appLaunchLogic) appLaunchLogicThread.Start() End Sub </code></pre> <p>TIA.</p>

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