How to open a dynamically created a xml data in Internet Explorer?

I read XML file:

string strFileName = @"D:\BigFile.xml";
XmlDocument xDoc = new XmlDocument();
xDoc.Load(strFileName);

I inserted a xml node into this xml file:

XmlNode xElt = xDoc.SelectSingleNode("pagina");
XmlElement xNewChild = xDoc.CreateElement("postPaginaXMLXMLXMLXMLXMLXMLXMLXML");
xDoc.DocumentElement.InsertBefore(xNewChild, xElt);

However, I couldn't opend this xDoc in Internet Explorer. I can open a created file:

Process proc = new Process();
proc.StartInfo.UseShellExecute = true;
proc.StartInfo.FileName = strFileName;
proc.Start();

But, this code opens a real xml file by address(strFileName). How to open a dynamically created xml file in Internet Explorer without saving/creating this file on HDD?