check if a url exists

reggiepangilinanX

is there a way to check if a url or a website exists

timvw

Use HttpWebRequest and check the statusCode in the HttpWebResponse... (A HEAD instead of a GET request is sufficient to do this)

eg:

Code Snippet

Uri uri = new Uri("http://www.timvw.be");
HttpWebRequest httpWebRequest = WebRequest.Create(uri) as HttpWebRequest;
httpWebRequest.Method = "HEAD";
httpWebRequest.AllowAutoRedirect = true;
// we'll use the Async pattern...
httpWebRequest.BeginGetResponse(this.GetResponseCompleted, new object[] { httpWebRequest, uri });

private void GetResponseCompleted(IAsyncResult ar)
{
object[] objects = ar.AsyncState as object[];
HttpWebRequest httpWebRequest = objects[0] as HttpWebRequest;
Uri uri = objects[1] as Uri;

HttpWebResponse httpWebResponse = null;
int httpStatusCode;

try
{
httpWebResponse = httpWebRequest.EndGetResponse(ar) as HttpWebResponse;
httpStatusCode = (int)httpWebResponse.StatusCode;
}
catch (WebException webException)
{
httpWebResponse = webException.Response as HttpWebResponse;
if (httpWebResponse != null)
{
httpStatusCode = (int)httpWebResponse.StatusCode;
}
}
finally
{

if (httpStatusCode == 200 ) { Console.WriteLine("the resource exists"); }

if (httpWebResponse != null)
{
httpWebResponse.Close();
}
}
}

}

reggiepangilinanX

i've tried your code and it returns an exception

"Proxy Authentication Required ( The ISA Server requires authorization to fulfill the request. Access to the Web Proxy service is denied. )"

what is the meaning of this

element109

Code Snippet

'This code attempts to get a response from the passed URL.

Friend Function WebSiteIsAvailable(ByVal linkText As String) As Boolean

Dim URL_Object As New System.Uri(linkText)

Dim URL_WebRequest As System.Net.WebRequest

Dim URL_WebResponse As System.Net.WebResponse

Dim Response_Result As Boolean

Try

URL_WebRequest = System.Net.WebRequest.Create(URL_Object)

URL_WebResponse = URL_WebRequest.GetResponse

Response_Result = True

Catch

Response_Result = False

End Try

URL_WebResponse = Nothing

URL_WebRequest = Nothing

URL_Object = Nothing

Return Response_Result

End Function

timvw

reggiepangilinanX wrote:

"Proxy Authentication Required ( The ISA Server requires authorization to fulfill the request. Access to the Web Proxy service is denied. )"

what is the meaning of this

It means that you have a proxy server in between that requires you to authenticate.. In most situations it's sufficient add the DefaultNetworkCredentials to the httpWebRequest instance before you perform the request:

Code Snippet

httpWebRequest.Credentials = CredentialCache.DefaultNetworkCredentials;
httpWebRequest.GetResponse();

check if a url exists

Re: .NET Framework Networking and Communication check if a url exists

Re: .NET Framework Networking and Communication check if a url exists

Re: .NET Framework Networking and Communication check if a url exists

Re: .NET Framework Networking and Communication check if a url exists