web-services - webrequest.create（URL）でのNUll参照例外

Question

行にnull参照例外がありますwebrequest.create(v_strURL)

Dim objHttpWebRequest As HttpWebRequest
        Dim objHttpWebResponse As HttpWebResponse
        Dim objRequestStream As Stream = Nothing
        Dim objResponseStream As Stream = Nothing

        Dim objXMLReader As XmlTextReader

        objHttpWebRequest = CType((WebRequest.Create(v_strURL)), HttpWebRequest) ''This line throws exception.

はUrl正しく、適切な応答を示します。