Question

I have a function which is taking a lot of time to execute in a web application.

I have tested this with a profiler and by my logging.

I have other functions running in the same pageload.

What is a best way to display the rest of the values from those functions and keep this function in a thread and display it in a label when it finishes?

This function is used to get events in application which takes time.

private void getEventErrors()
    {
        EventLog eventLog = new EventLog("Application", ".");

        getEvents(eventLog.Entries);
    }

private void getEvents(EventLogEntryCollection eventLogEntryCollection)
    {
        int errorEvents = 0;

        foreach (EventLogEntry logEntry in eventLogEntryCollection)
        {
            if (logEntry.Source.Equals("XYZ"))
            {
                DateTime variable = Convert.ToDateTime(logEntry.TimeWritten);
                long eventTimeTicks = (variable.Ticks);
                long eventTimeUTC = (eventTimeTicks - 621355968000000000) / 10000000;

                long presentDayTicks = DateTime.Now.Ticks;
                long daysBackSeconds = ((presentDayTicks - 864000000000) - 621355968000000000) / 10000000;


                if (eventTimeUTC > daysBackSeconds)
                {
                    if (logEntry.EntryType.ToString() == "Error")
                    {
                        errorEvents = errorEvents + 1;
                    }                        
                }
            }
        }
        btn_Link_Event_Errors_Val.Text = errorEvents.ToString(GUIUtility.TWO_DECIMAL_PT_FORMAT);            
        if (errorEvents == 0)
        {
            lbl_EventErrorColor.Attributes.Clear();
            lbl_EventErrorColor.Attributes.Add("class", "green");
        }
        else
        {
            lbl_EventErrorColor.Attributes.Clear();
            lbl_EventErrorColor.Attributes.Add("class", "red");
        }
    }

I have 3 functions in the pageload event, two to get the values from the DB and the other one is shown above.

Should both these functions be service calls?

What i wanted was, the page should load fast and if there is a function taking a lot of time it should run in the background and display when done and in the process if the user want to navigate to a new page it should kill it and move on.

Answer 1

If you have a function that is running in a separate thread in ASP.NET, you may want to consider moving it to a service. There are many reason for this

See this answer (one of many on SO) for why running long running tasks in ASP.NET is not always a good idea.

One option for the service is to use WCF. You can get started here. Your service could implement a method, say GetEvents() which you could use to pull your events. That way you won’t tie up your page waiting for this process to complete (using AJAX of course). Also, this allows you to change your implementation of GetEvents() without touching your code on your website.