log files and adding custom headers

in win2012r2, in the iis , there is new ability to add custom headers.

is there a way to write to the log file the soap request?

today i do it using c# code (and then appendToLog):

 XmlDocument xmlSoapRequest = new XmlDocument();

            // Get raw request body
            Stream receiveStream = HttpContext.Current.Request.InputStream;

            // Move to beginning of input stream and read
            receiveStream.Position = 0;
            using (StreamReader readStream = new StreamReader(receiveStream, Encoding.UTF8))
            {
                // Load into XML document
                xmlSoapRequest.Load(readStream);
            }

            return xmlSoapRequest.InnerXml;

is there any way to get the "stream" and write it to the log file?