Develop Reference

Open a webpage from console (C#) after 10 seconds

I'm writing a console application in C#. How can I open a webpage after 10 seconds? I already found something like
System.Diagnostics.Process.Start("http://www.stackoverflow.com")
but how can I add a timer?

You can choose from the below options depending on the application:
System.Timers.Timer
System.Windows.Forms.Timer
System.Threading.Timer
For example:
System.Threading.Thread.Sleep((int)System.TimeSpan.FromSeconds(10).TotalMilliseconds);

If you want to open this page every 10 seconds try this
Timer timer = new Timer();
timer.Interval = 10000;
timer.Tick += timer_Tick;
timer.Start();
void timer_Tick(object sender, EventArgs e)
{
System.Diagnostics.Process.Start("http://www.stackoverflow.com");
timer.Stop(); //If you don't want to show page every 10 seconds stop the timer once it has shown the page.
}
And if you want it to only show page once than you can stop the timer by using Stop() method of timer class.

Since you are trying to open url within C# using
System.Diagnostics.Process.Start I am suggesting you to read this, I copy-paste the code posted in that webpage, in case the link will be broken in same day:
public void OpenLink(string sUrl)
{
try
{
System.Diagnostics.Process.Start(sUrl);
}
catch(Exception exc1)
{
// System.ComponentModel.Win32Exception is a known exception that occurs when Firefox is default browser.
// It actually opens the browser but STILL throws this exception so we can just ignore it. If not this exception,
// then attempt to open the URL in IE instead.
if (exc1.GetType().ToString() != "System.ComponentModel.Win32Exception")
{
// sometimes throws exception so we have to just ignore
// this is a common .NET bug that no one online really has a great reason for so now we just need to try to open
// the URL using IE if we can.
try
{
System.Diagnostics.ProcessStartInfo startInfo = new System.Diagnostics.ProcessStartInfo("IExplore.exe", sUrl);
System.Diagnostics.Process.Start(startInfo);
startInfo = null;
}
catch (Exception exc2)
{
// still nothing we can do so just show the error to the user here.
}
}
}
}
Regarding the suspended execution please use Task.Delay:
var t = Task.Run(async delegate
{
await Task.Delay(TimeSpan.FromSeconds(10));
return System.Diagnostics.Process.Start("http://www.stackoverflow.com");
});
// Here you can do whatever you want without waiting to that Task t finishes.
t.Wait();// that's is a barrier and the code after t.Wait() will be executed only after t had returned.
Console.WriteLine("Task returned with process {0}, t.Result); // in case System.Diagnostics.Process.Start fails t.Result should be null

C# Windows Service won't start

When I try to start my c# service it says:"starting" for a second and it turns back to being "stopped"
What can be the problem? I had the same code before, and it worked but made some changes in the code now and it stopped working. Here is what I added to my code:
App Config:
<add key="cut-copy" value="copy"/>
Normal code:
private void fileSystemWatcher1_Created(object sender, System.IO.FileSystemEventArgs e)
{
String cut_copy = ConfigurationManager.AppSettings[#"cut-copy"];
if (cut_copy == "copy")
{
cut = false;
}
else
{
cut = true;
}
if (WaitForFileAvailable(e.FullPath, TimeSpan.FromSeconds(10)))
{
var file = Path.Combine(source, e.Name);
var copy_file = Path.Combine(target, e.Name);
var destination = Path.Combine(target, Path.ChangeExtension(source, Path.GetExtension(source)));
if (File.Exists(file))// Check to see if the file exists.
{ //If it does delete the file in the target and copy the one from the source to the target.
File.Delete(copy_file);
File.Copy(e.FullPath, Path.Combine(target, e.Name));
}
else// If it doesn't, just copy the file.
{
if (cut == true)
{
if (File.Exists(file))// Check to see if the file exists.
{ //If it does delete the file in the target and copy the one from the source to the target.
File.Delete(copy_file);
File.Move(Path.Combine(e.FullPath, e.Name), target);
}
}
else
{
if (File.Exists(file))// Check to see if the file exists.
{ //If it does delete the file in the target and copy the one from the source to the target.
File.Delete(copy_file);
File.Copy(e.FullPath, Path.Combine(target, e.Name));
}
}
//under this is more code that didn't change
}
EDIT: ONSTART:
protected override void OnStart(string[] args)
{
base.OnStart(args);
this.fileSystemWatcher1 = new System.IO.FileSystemWatcher();
((System.ComponentModel.ISupportInitialize)(this.fileSystemWatcher1)).BeginInit();
fileSystemWatcher1.Path = source;
fileSystemWatcher1.Changed += new FileSystemEventHandler(fileSystemWatcher1_Changed);
fileSystemWatcher1.Created += new FileSystemEventHandler(fileSystemWatcher1_Created);
fileSystemWatcher1.Deleted += new FileSystemEventHandler(fileSystemWatcher1_Deleted);
fileSystemWatcher1.Renamed += new RenamedEventHandler(fileSystemWatcher1_Renamed);
this.fileSystemWatcher1.EnableRaisingEvents = true;
this.fileSystemWatcher1.IncludeSubdirectories = true;
((System.ComponentModel.ISupportInitialize)(this.fileSystemWatcher1)).EndInit();
logger("Service started "+ DateTime.Now);
}
What am I doing wrong?

Usually this behavior indicates that the OnStart method ends without leaving any threads running. I have experienced that if an unhandled exception is thrown starting the service, the service doesn't go into Stopped state, but the service manager shows the "Starting service" window for 30 seconds and then fails saying it can't determine the service's state.
I'm not sure whether the FileSystemWatcher actually spawns a new thread that keeps running. You could (just to try it), also create a System.Timers.Timer that fires every 30 seconds in OnStart and stop that timer in OnStop. If the service keeps running then, you have to spawn a new thread for the FileSystemWatcher.
Usually, in OnStart you'd spawn a separate thread that does the service's work. Be it waiting for TCP connections, a timer that does things on a regular basis or any other kind of thread. If you don't do that, the service just stops as soon as there are no more threads active.

For the code, the only answer that anyone could give you are just "guessing". You better debug it yourself.
The easiest way to hit a break-point in a Windows Service is to put this line of code at the beginning of the OnStart method:
Debugger.Break();
Compile your service in Debug mode, so you can have all the necessary symbols in your executable.
Install your service
Start it from the service list.
You will get a prompt for debugging the "yourservicename.exe" program.
Say Yes-debug, Choose debugger.
Choose the correct Visual Studio version as your debugger.
Now you will be in the Debugger.Break line
Have fun

Making a infinite loop in .Net MVC

I need a operations which needs to run every x seconds forever, and to achieve this I did:
protected void Application_Start()
{
InitialieOnce.Initialize();
}
public static class InitialieOnce
{
private static bool initialized = false;
public static void Initialize()
{
if (initialized == false)
{
initialized = true;
Thread t = new Thread(x => CheckStatus());
t.IsBackground = true;
t.Start();
}
}
private static void CheckStatus()
{
//My script goes here.
Thread.Sleep(8000);
CheckStatus();
}
}
After some time (about 5 minutes) I get this error:
"An unhandled exception of type 'System.StackOverflowException' occurred in mscorlib.dll"
Can this error be related to how I made my infinite loop?
If yes, is there a better way to achieve this, can I fix it, or is this code ok?

You are calling "CheckStatus" recursively. So every 8 seconds there will be one more entry on your call stack:
CheckStatus() -> CheckStatus() -> CheckStatus() -> and so on.. until you get a StackOverflowException.
Instead you should use
while (true)
{
/* Your Code */
Thread.Sleep(8000);
}
Please also note that by default IIS will unload your application if there was no request in 15 minutes, resulting in your thread being killed.

Consider creating a Windows service for such a thing, instead of abusing IIs..
I don't know where, but I read that IIs isn't good for creating long living services like in javas servers.

I would also suggest creating a Windows service for that, something like a daemon. You can create a service that will just call a special action on your application on regular intervals. The rest of the work will be done within your MVC application. Have a look at this post for an example.

Multiple InfoPath interop automation instances

I am trying to automate multiple parallel instances of Office InfoPath 2010 via a windows service. I understand automating Office from a service is not supported however it is a requirement of my customer.
I can automate other Office applications in a parallel fashion, however InfoPath behaves differently.
What I have found is that there will only ever be one instance of the INFOPATH.EXE process created, no matter how many parallel calls to CreateObject("InfoPath.Application") are made. In contrast to this, multiple instances of WINWORD.EXE can be created via the similar mechanism CreateObject("Word.Application")
To reproduce this issue, a simple console application can be used.
static void Main(string[] args) {
// Create two instances of word in parallel
ThreadPool.QueueUserWorkItem(Word1);
ThreadPool.QueueUserWorkItem(Word2);
System.Threading.Thread.Sleep(5000);
// Attempt to create two instances of infopath in parallel
ThreadPool.QueueUserWorkItem(InfoPath1);
ThreadPool.QueueUserWorkItem(InfoPath2);
}
static void Word1(object context) {
OfficeInterop.WordTest word = new OfficeInterop.WordTest();
word.Test();
}
static void Word2(object context) {
OfficeInterop.WordTest word = new OfficeInterop.WordTest();
word.Test();
}
static void InfoPath1(object context) {
OfficeInterop.InfoPathTest infoPath = new OfficeInterop.InfoPathTest();
infoPath.Test();
}
static void InfoPath2(object context) {
OfficeInterop.InfoPathTest infoPath = new OfficeInterop.InfoPathTest();
infoPath.Test();
}
The InfoPathTest and WordTest classes (VB) are in another project.
Public Class InfoPathTest
Public Sub Test()
Dim ip As Microsoft.Office.Interop.InfoPath.Application
ip = CreateObject("InfoPath.Application")
System.Threading.Thread.Sleep(5000)
ip.Quit(False)
End Sub
End Class
Public Class WordTest
Public Sub Test()
Dim app As Microsoft.Office.Interop.Word.Application
app = CreateObject("Word.Application")
System.Threading.Thread.Sleep(5000)
app.Quit(False)
End Sub
End Class
The interop classes simply create the automation objects, sleep and then quit (although in the case of Word, I have completed more complex tests).
When running the console app, I can see (via Task Manager) two WINWORD.EXE processes created in parallel, and only a single INFOPATH.EXE process created. In fact when the first instance of InfoPathTest calls ip.Quit, the INFOPATH.EXE process terminates. When the second instance of InfoPathTest calls ip.Quit, a DCOM timeout exception is thrown - it appears as though the two instances were sharing the same underlying automation object, and that object no longer exists after the first call to ip.Quit.
At this stage my thoughts were only a single INFOPATH.EXE is supported per user login. I expanded the windows service to start two new processes (a console application called InfoPathTest), each running under a different user account. These new processes would then attempt to automate INFOPATH.EXE
Here's where it gets interesting, this actually works, but only on some machines, and I cannot figure out why that is the case.
And the service code (with help from AsproLock):
public partial class InfoPathService : ServiceBase {
private Thread _mainThread;
private bool isStopping = false;
public InfoPathService() {
InitializeComponent();
}
protected override void OnStart(string[] args) {
if (_mainThread == null || _mainThread.IsAlive == false) {
_mainThread = new Thread(ProcessController);
_mainThread.Start();
}
}
protected override void OnStop() {
isStopping = true;
}
public void ProcessController() {
while (isStopping == false) {
try {
IntPtr hWinSta = GetProcessWindowStation();
WindowStationSecurity ws = new WindowStationSecurity(hWinSta, System.Security.AccessControl.AccessControlSections.Access);
ws.AddAccessRule(new WindowStationAccessRule("user1", WindowStationRights.AllAccess, System.Security.AccessControl.AccessControlType.Allow));
ws.AddAccessRule(new WindowStationAccessRule("user2", WindowStationRights.AllAccess, System.Security.AccessControl.AccessControlType.Allow));
ws.AcceptChanges();
IntPtr hDesk = GetThreadDesktop(GetCurrentThreadId());
DesktopSecurity ds = new DesktopSecurity(hDesk, System.Security.AccessControl.AccessControlSections.Access);
ds.AddAccessRule(new DesktopAccessRule("user1", DesktopRights.AllAccess, System.Security.AccessControl.AccessControlType.Allow));
ds.AddAccessRule(new DesktopAccessRule("user2", DesktopRights.AllAccess, System.Security.AccessControl.AccessControlType.Allow));
ds.AcceptChanges();
ThreadPool.QueueUserWorkItem(Process1);
ThreadPool.QueueUserWorkItem(Process2);
} catch (Exception ex) {
System.Diagnostics.Debug.WriteLine(String.Format("{0}: Process Controller Error {1}", System.Threading.Thread.CurrentThread.ManagedThreadId, ex.Message));
}
Thread.Sleep(15000);
}
}
private static void Process1(object context) {
SecureString pwd2;
Process process2 = new Process();
process2.StartInfo.FileName = #"c:\debug\InfoPathTest.exe";
process2.StartInfo.UseShellExecute = false;
process2.StartInfo.LoadUserProfile = true;
process2.StartInfo.WorkingDirectory = #"C:\debug\";
process2.StartInfo.Domain = "DEV01";
pwd2 = new SecureString(); foreach (char c in "password") { pwd2.AppendChar(c); };
process2.StartInfo.Password = pwd2;
process2.StartInfo.UserName = "user1";
process2.Start();
process2.WaitForExit();
}
private static void Process2(object context) {
SecureString pwd2;
Process process2 = new Process();
process2.StartInfo.FileName = #"c:\debug\InfoPathTest.exe";
process2.StartInfo.UseShellExecute = false;
process2.StartInfo.LoadUserProfile = true;
process2.StartInfo.WorkingDirectory = #"C:\debug\";
process2.StartInfo.Domain = "DEV01";
pwd2 = new SecureString(); foreach (char c in "password") { pwd2.AppendChar(c); };
process2.StartInfo.Password = pwd2;
process2.StartInfo.UserName = "user2";
process2.Start();
process2.WaitForExit();
}
[DllImport("user32.dll", SetLastError = true)]
public static extern IntPtr GetProcessWindowStation();
[DllImport("user32.dll", SetLastError = true)]
public static extern IntPtr GetThreadDesktop(int dwThreadId);
[DllImport("kernel32.dll", SetLastError = true)]
public static extern int GetCurrentThreadId();
}
The InfoPathTest.exe process simply calls the InfoPathTest.Test() method detailed above.
In summary, this works, but only on certain machines. When it fails, the second INFOPATH.EXE process is actually created, but immediately quits with an exitcode of 0. There is nothing in the event logs, nor any exceptions in the code.
I've looked at many things to try and differentiate between working / non working machines, but I'm now stuck.
Any pointers appreciated, especially if you have other thoughts on how to automate multiple InfoPath instances in parallel.

I'm guessing you'd get similar behavior if you tried to do the same thing with Outlook, which would mean Microsoft thinks it is a bad idea to run multiple copies.
If that is so, I see two options.
Option one is to make your Infopath automation synchronous, running one instance at a time.
Option two, and I have NO idea if it would even work, would be to see if you can launch virtual machines to accomplish youe InfoPath work.
I hope this can at least spark some new train of though that will lead to success.

I’ve encountered a very similar issue with Outlook. The restriction of allowing only a single instance of the application to be running does not apply per user, but per interactive login session. You may read more about it in Investigating Outlook's Single-Instance Restriction:
Outlook was determining whether or not another instance was already running in the interactive login session. […] During Outlook's initialization, it checks to see if a window named "Microsoft Outlook" with class name "mspim_wnd32" exists, and if so, it assumes that another instance is already running.
There are ways of hacking around it – there is a tool for launching multiple Outlook instances on the Hammer of God site (scroll down) – but they will probably involve intercepting Win32 calls.
As for your code only working on certain machines: That’s probably due to a race condition. If both processes manage to start up fast enough simultaneously, then they won’t detect each other’s window, and assume that they’re the only instance running. However, if the machine is slow, one process would open its window before the other, thereby causing the second process to detect the first process’s window and shut itself down. To reproduce, try introducing a delay of several seconds between launching the first process and the second – this way, only the first process should ever succeed.

C# Window Service and Starting/Stopping cmd.exe

I have a C# Window Service that runs a batch file (.bat) which in turn, executes a java app. The service runs the .bat file (cmd.exe) with no problem. However, when I try to stop the window service, the cmd.exe process does not die. A new cmd process is stacked if I start the service again.
How do I kill the running cmd.exe process?
Code:
private const string BATCH_FILE_PATH_APPKEY = "Service_Batch_File_Path";
private const string BATCH_FILE_DEFAULT = "Service.bat";
private static Process _proc;
private static bool _hasStarted = false;
public AService()
{
InitializeComponent();
_proc = new Process();
}
protected override void OnStart(string[] args)
{
try
{
string appDirectory = System.Windows.Forms.Application.ExecutablePath;
appDirectory = appDirectory.Substring(0, appDirectory.LastIndexOf("\\"));
string workingDirectory = appDirectory;
string batchFilePath = string.Empty;
batchFilePath = workingDirectory + "Service.bat";
// Make sure it exists
_proc.StartInfo = new ProcessStartInfo(batchFilePath);
_proc.StartInfo.CreateNoWindow = true;
_proc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
_proc.Start();
_hasStarted = true;
}
catch (System.Exception ex)
{
eventLog1.WriteEntry(ex.ToString() + "\n\nStack Trace:\n" + ex.StackTrace);
OnStop();
}
}
protected override void OnStop()
{
if (_hasStarted)
_proc.CloseMainWindow();
//_proc.Close();
}
TIA,
Alex.

_proc.Kill();
See the details in MSDN: Process.Kill Method
You may find the following link very useful: Process.Close() is not terminating created process,c#

_proc.Kill () will work.... but it will orphan your java app. I have done something similar where a third process was started. You will also need to know which java process to kill. To do this, you can use the ParentProcess Performance Counter.
Here are some details on using the ParentProcess performance counter.
Also, version of Windows do you plan to deploy this on? WindowsServer2008 seems to have a cmd.exe and a conhost.exe. That may pose a problem for you (again one that can probably be resolved by knowing the parent process.

Have you tried _proc.Kill() in your service's closedown processing? This is async and you should then call WaitForExit to give it a decent chance to go away. Log any failures or exceptions in this logic for investigation.
You should also (for cleanliness) reinstate the _proc.Close() after calling WaitForExit(), to ensure Dispose() gets called properly for the Process. I know your service is about to exit, but this is a good habit and means you are less likely to leak if you decide to manage the child Process more dynamically in future.