How to trigger a windows service to start when new folder or file created

Question

I have a windows service that prints reports on start.I have two scenarios-
1.I want to start this service when a new folder has been created in my E:\here\ folder.How to accomplish this?
2 Also is it possible to trigger a service when a new row inserted into database table?how?

Please provide links for above queries.

Answer 1

You can use a FileSystemWatcher to check if the specific folder is created in a specific location. When its created you can start the Windows Service.

Creating FileSystemWatcher

//Define this in the clas level
FileSystemWatcher watcher = new FileSystemWatcher();

Initializing

private void InitializeWatcher()
{ 
  watcher.Created += new FileSystemEventHandler(NotifyChange);
  watcher.Path = @"E:\here\folder";
  watcher.EnableRaisingEvents = true;
}

Starting Windows Service when folder is created

private void NotifyChange(object sender, FileSystemEventArgs e)
{
   if (e.Name.Equals("FolerName",StringComparison.OrdinalIgnoreCase))
   {
      new ServiceController("WindowsServiceName").Start();
   }
}

Answer 2

You can create a new service which polls for new records and/or new folders, and then starts the existing service accordingly.

For the database, most likely you'd simply verify the row count or the latest ID in a given table periodically, for instance every 5 seconds or whatever your acceptable window is. If your database is a SQL Server database, you can also use the SqlDependency class. There is more about that on MSDN (http://msdn.microsoft.com/en-us/library/62xk7953(v=vs.110).aspx) and the Code Project (http://www.codeproject.com/Articles/12335/Using-SqlDependency-for-data-change-events).

For the folder, you can use the FileSystemWatcher class to notify you of any changes (here is an example of how to do that: http://snipplr.com/view/54606).