You're not calling Dispose
on the HttpWebResponse
object, which means that the connection is still lying around. If you change your code to the following:
public static string isAlive(string url)
{
Console.WriteLine("start: Is Alive Test");
WebRequest request = WebRequest.Create(url);
try
{
using(HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
return Convert.ToString((int)response.StatusCode);
}
}
catch(WebException ex)
{
using(HttpWebResponse res = (HttpWebResponse)ex.Response)
{
return Convert.ToString((int)res.StatusCode);
}
}
}
the using
statement will implicitly call Dispose for you, which will close the connection.
The reason your code is halting after the second iteration is because .Net has a built in maximum number of connections it will open to a website, which is by default 2. This is controlled by System.Net.ServicePointManager.DefaultConnectionLimit
which you can increase should you need to.