Redirecting to www - asp.net

Question

I've added a global.asax to my web project, and I'm trying to check if the domain in the Begin_Request contains "www", and if it doesn't, then redirect them to the page they were requesting, but with the "www" pre-pended to it. For an example, If I try to access : SampleSite.com, it directs me to SampleSite.com/www.SampleSite.com/www.SampleSite.com/www.SampleSite.com/www.SampleSite.com/www.SampleSite.com/www.SampleSite.com/www.SampleSite.com/index.aspx
Here is the code:
<script runat="server">
Sub Begin_Request(ByVal sender As Object, ByVal e As EventArgs) Handles Me.BeginRequest
Dim domain As String = Request.Url.Host
If (Not domain.StartsWith("www")) Then
Dim path As String = ""
path = String.Format("www.{0}", Request.Url.AbsoluteUri.Substring(7))
Response.Redirect(path)
End If
End Sub
</script>
Any ideas?

Answer 1

I don't think you should do this by code but using IIS redirect features. Here you have an example about how to do it on IIS 7
In case you still want to stay with this approach, change
String.Format("www.{0}", Request.Url.AbsoluteUri.Substring(7));
by
String.Format("{0}://www.{1}", Request.Url.Scheme, Request.Url.AbsoluteUri.Substring(7));