Best way to test if a website is alive from a C# applicaiton

Question

I am looking for the best way to test if a website is alive from a C# application.

Background
My application consists of a Winforms UI, a backend WCF service and a website to publish content to the UI and other consumers. To prevent the situation where the UI starts up and fails to work properly because of a missing WCF service or website being down I have added an app startup check to ensure that all everything is alive.

The application is being writen in C#, .Net 3.5, Visual Studio 2008 SP1

Current Solution
Currently I am making a web request to a test page on the website that will inturn test the web site and then display a result.

WebRequest request = WebRequest.Create("http://localhost/myContentSite/test.aspx");
WebResponse response = request.GetResponse();

I am assuming that if there are no exceptions thown during this call then all is well and the UI can start.

Question
Is this the simplest/ right way or is there some other shneaky call that I do no know about in C# or a better way to do it.

Answer 1

You'll want to check the status code for OK (status 200).

Answer 2

HttpWebResponse response = (HttpWebResponse)request.GetResponse();
if (response == null || response.StatusCode != HttpStatusCode.OK)

Answer 3

Assuming the WCF service and the website live in the same web app, you can use a "Status" WebService that returns the application status. You probably want to do some of the following:

• Test that the database is up and running (good connection string, service is up, etc...)
• Test that the website is working (how exactly depends on the website)
• Test that WCF is working (how exactly depends on your implementation)
• Added bonus: you can return some versioning info on the service if you need to support different releases in the future.

Then, you create a client on the Win.Forms app for the WebService. If the WS is not responding (i.e. you get some exception on invoke) then the website is down (like a "general error").
If the WS responds, you can parse the result and make sure that everything works, or if something is broken, return more information.

Answer 4

from the NDiagnostics project on CodePlex...

public override bool WebSiteIsAvailable(string Url)
{
  string Message = string.Empty;
  HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(Url);

  // Set the credentials to the current user account
  request.Credentials = System.Net.CredentialCache.DefaultCredentials;
  request.Method = "GET";

  try
  {
    using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
    {
      // Do nothing; we're only testing to see if we can get the response
    }
  }
  catch (WebException ex)
  {
    Message += ((Message.Length > 0) ? "\n" : "") + ex.Message;
  }

  return (Message.Length == 0);
}

Answer 5

While using WebResponse please make sure that you close the response stream ie (.close) else it would hang the meachine after certain repeated execution. Eg

            HttpWebRequest req = (HttpWebRequest)WebRequest.Create(sURL);
            HttpWebResponse response = (HttpWebResponse)req.GetResponse();
            // your code here
            response.close();