Hi, Someone else has already asked a somewhat similar question: http://stackoverflow.com/questions/1888887/validate-an-xml-file-against-a-dtd-with-a-proxy-c-2-0/2766197#2766197

Here's my problem: We have a website application that needs to use both internal and external resources.

1. We have a bunch of internal webservices. Requests to the CANNOT go through the proxy. If we try to, we get 404 errors since the proxy DNS doesn't know about our internal webservice domains.
2. We generate a few xml files that have to be valid. I'd like to use the provided dtd documents to validate the xml. The dtd urls are outside our network and MUST go through the proxy.

Is there any way to validate via dtd through a proxy without using system.net.defaultproxy? If we use defaultproxy, the internal webservices are busted, but the dtd validation works.#

Here is what I'm doing to validate the xml right now:

public static XDocument ValidateXmlUsingDtd(string xml)
{
    var xrSettings = new XmlReaderSettings {
        ValidationType = ValidationType.DTD,
        ProhibitDtd = false
    };

    var sr = new StringReader(xml.Trim());

    XmlReader xRead = XmlReader.Create(sr, xrSettings);
    return XDocument.Load(xRead);
}

Ideally, there would be some way to assign a proxy to the XmlReader much like you can assign a proxy to the HttpWebRequest object. Or perhaps there is a way to programatically turn defaultproxy on or off? So that I can just turn it on for the call to Load the Xdocument, then turn it off again?

FYI - I'm open to ideas on how to tackle this - note that the proxy is located in another domain, and they don't want to have to set up a dns lookup to our dns server for our internal webservice addresses.

Cheers, Lance