The remote host could not be resolved:

I have the following C# program:

using System;
using System.IO;
using System.Net;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            string sourceUri = "http://tinyurl.com/22m56h9";

            var request = WebRequest.Create(sourceUri);
            try
            {
                //Edit: request = WebRequest.Create(sourceUri);
                request.Method = "HEAD";

                var response = request.GetRespons开发者_如何学运维e();
                if (response != null)
                {
                    Console.WriteLine(request.GetResponse().ResponseUri);
                }
            }
            catch (Exception exception) {
                Console.WriteLine(exception.Message);                
            }
            Console.Read();
        }
    }    
}

If a run my program, with the sourceUri = "http://tinyurl.com/22m56h9" everithing is OK, i just get the destination of the tinyurl link.

But if a run my program with tinyurl link that redirects to a site that is marked as malware, my code throws an exception saying The remote host could not be resolved: '...'. I need to get the uri of the malware link, because i want to make an application that search some test for link and returns if they are malware or not, and if a link is minified (the case above), i need to know where is redirecting to.

So my question is Am i doing something wrong in my code? or Is there a better aproach on testing if a link is a redirect or not? Thank in advance

Instead of a catching a general Exception you should try catching a WebException object instead. Something like:

try
{
    request.Method = "HEAD";

    var response = request.GetResponse();
    if (response != null)
    {
        Console.WriteLine(request.GetResponse().ResponseUri);
    }
}
catch (WebException webEx) {
    // Now you can access webEx.Response object that contains more info on the server response              
   if(webEx.Status == WebExceptionStatus.ProtocolError) {
        Console.WriteLine("Status Code : {0}", ((HttpWebResponse)webEx.Response).StatusCode);
        Console.WriteLine("Status Description : {0}", ((HttpWebResponse)webEx.Response).StatusDescription);
    }
}
catch (Exception exception) {
    Console.WriteLine(exception.Message);                
}

The WebException contains a Response object that you can access to find out more information about what the server actually returned.

You may be interested in reading server response codes (HTTP headers). A redirect is usually done by them.

http://en.wikipedia.org/wiki/List_of_HTTP_status_codes#3xx_Redirection