Question

I am creating an Intranet webpage for my office.

The application needs to download SMTP email every 5 minutes. (As well as some other house keeping things)

I have just created a ASP.NET webpage that is running on IIS through Windows 2008 R2 server.

Do I have to create a seperate Windows Service to do this? So I would just have 2 programs, the webpage and the windows service?

or is there a better way to do it?

Answer 1

The idea

The simplest way to do recurring stuffs on an asp.net web site is

• During the application start, create an instance of System.Timers.Timer object and keep it reference on a static field in your code (to prevent garbage collection)
• Make it to AutoReset and give it the interval you want (5min)
• Listen to the Elapsed event and put your recurring tasks there

The code

public class Global : System.Web.HttpApplication
{
    private static Timer timer;

    protected void Application_Start(object sender, EventArgs e)
    {
        timer = new Timer(5 * 60 * 1000);
        timer.AutoReset = true;
        timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
    }

    void timer_Elapsed(object sender, ElapsedEventArgs e)
    {
        //Get our emails here
    }
}

About the app pool recycle

It does not matter:

• If your site have traffic, then the app pool will stay up
• If there are timespans where there is no traffic, the app pool may be stop but you don’t care because there are no users to complain about that 🙂

If it’s really important, know that by default, an app pool is configured to recycle just once a day and to not stop even if there are no traffic.