C# - HttpWebResponse redirect checker

Question

I'm trying to code a redirect checker, the solution I have was just banged together this morning so it's not the most efficient but it does everything I need it to do apart from one thing:

It only ever checks two sites before stopping, no errors occur, it just stops on the "request.GetResponse() as HttpWebResponse;" line for the third page.

I've tried using different sites and changing the combination of pages to check but it only ever checks two.

Any ideas?

        string URLs = "/htmldom/default.asp/htmldom/dom_intro.asp/htmldom/dom_examples2.asp/xpath/default.asp";
        string sURL = "http://www.w3schools.com/";
        string[] u = Regex.Split(URLs, ".asp");

        foreach (String site in u)
        {
            String superURL = sURL + site + ".asp";

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(superURL);

            request.Method = "HEAD";
            request.AllowAutoRedirect = false;

            var response = request.GetResponse() as HttpWebResponse;
            String a = response.GetResponseHeader("Location");

            Console.WriteLine("Site: " + site + "\nResponse Type: " + response.StatusCode + "\nRedirect page" + a + "\n\n");
        }

Jon Skeet · Accepted Answer · 2013-03-21 10:52:24Z

5

Aside from the fact that it will break if a WebException is ever thrown, I believe the reason it's just stopping is that you never dispose of your response. If you have multiple URLs served actually by the same site, they'll use a connection pool - and by not disposing of the response, you're not releasing the connection. You should use:

using (var response = request.GetResponse())
{
    var httpResponse = (HttpWebResponse) response;
    // Use httpResponse here
}

Note that I'm casting here instead of using as - if the response isn't an HttpWebResponse, an InvalidCastException on that line is more informative than a NullReferenceException on the next line...

answered Mar 21, 2013 at 10:52

Jon Skeet

1.5m893 gold badges9.3k silver badges9.3k bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Shane Callanan Over a year ago

Thanks Jon, after putting in some error handling code, your solution worked perfectly

Collectives™ on Stack Overflow

C# - HttpWebResponse redirect checker

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related