Usage Tracking with Google Analytics

analytics.cs

public class TrackingService
{
	// Sample usage:
	//     service.TrackEvent("customers/add");
	//     service.TrackEvent("order/discount-applied");
	public void TrackEvent(string path)
	{
		ThreadPool.QueueUserWorkItem(x => TrackPageView("/events/" + path));
	}

	private const string VERSION = "4.4sa";
	private static readonly int VISITOR = Guid.NewGuid().GetHashCode();

	private void TrackPageView(string path)
	{
		try
		{
			var connection = WebRequest.Create(GetGAUrl(path));

			((HttpWebRequest)connection).UserAgent = "";
			connection.Headers.Add("Accept-Language", "EN-US");

			using (connection.GetResponse())
			{
				// Ignore response
			}
		}
		catch 
		{
			// Swallow exception. It could be logged
		}
	}

	private static string GetGAUrl(string path)
	{
		const string DOMAIN = "mydomain.com";
		const string RESOURCE = "myapp";
		const string GA_ACCOUNT = "MO-111111-1";
		
		return "http://www.google-analytics.com/__utm.gif" + "?" +
			"utmwv=" + VERSION +
			"&utmn=" + GetRandomNumber() +
			"&utmhn=" + DOMAIN + 
			"&utmr=" + RESOURCE +  
			"&utmp=" + path.Replace("/", "%2F") +
			"&utmac=" + GA_ACCOUNT + 
			"&utmcc=__utma%3D999.999.999.999.999.1%3B" +
			"&utmvid=" + (VISITOR - DateTime.Today.GetHashCode());
	}

	private static string GetRandomNumber()
	{
		return new Random().Next(0x7fffffff).ToString();
	}
}