How to post XML document to HTTP with VB.Net - vb.net

Question

I'm looking for help with posting my XML document to a url in VB.NET. Here's what I have so far ...
Public Shared xml As New System.Xml.XmlDocument()
Public Shared Sub Main()
Dim root As XmlElement
root = xml.CreateElement("root")
xml.AppendChild(root)
Dim username As XmlElement
username = xml.CreateElement("username")
username.InnerText = _username
root.AppendChild(username)
xml.Save(Console.Out)
Dim url = "https://mydomain.com"
Dim req As WebRequest = WebRequest.Create(url)
req.Method = "POST"
req.ContentType = "application/xml"
req.Headers.Add("Custom: API_Method")
Console.WriteLine(req.Headers.ToString())
This is where things go awry:
I want to post the xml, and then print the results to console.
Dim newStream As Stream = req.GetRequestStream()
xml.Save(newStream)
Dim response As WebResponse = req.GetResponse()
Console.WriteLine(response.ToString())
End Sub

Answer 1

This is essentially what I was after:
xml.Save(req.GetRequestStream())

Answer 2

If you don't want to take care about the length, it is also possible to use the WebClient.UploadData method.
I adapted your snippet slightly in this way.
Imports System.Xml
Imports System.Net
Imports System.IO
Public Module Module1
Public xml As New System.Xml.XmlDocument()
Public Sub Main()
Dim root As XmlElement
root = xml.CreateElement("root")
xml.AppendChild(root)
Dim username As XmlElement
username = xml.CreateElement("username")
username.InnerText = "user1"
root.AppendChild(username)
Dim url = "http://mydomain.com"
Dim client As New WebClient
client.Headers.Add("Content-Type", "application/xml")
client.Headers.Add("Custom: API_Method")
Dim sentXml As Byte() = System.Text.Encoding.ASCII.GetBytes(xml.OuterXml)
Dim response As Byte() = client.UploadData(url, "POST", sentXml)
Console.WriteLine(response.ToString())
End Sub
End Module