It seems to me that the most practical use for a transformation is to transform an XML string that has been assembled from various data calls. This XML string would be the data for a web page or other user interface. There doesn't seem to be a lot of good examples out there of this. SO I put one together and would like some feedback from anyone that would like to improve upon it. Here is the code:
Public Class XForm
    Public Function ConvertXmlToHtml( _
        ByVal XmlString As String, _
        ByVal XslFileName As String _
    ) As String

        Dim utf8encoder As System.Text.UTF8Encoding = New System.Text.UTF8Encoding
        Dim inputInBytes() As Byte = utf8encoder.GetBytes(XmlString)
        Dim ms As New System.IO.MemoryStream(inputInBytes)
        Dim sr As System.IO.StreamReader
        Dim xslt As New System.Xml.Xsl.XslTransform
        Dim xpn As System.Xml.XPath.XPathNavigator
        Dim xpd As System.Xml.XPath.XPathDocument
        Dim rs As String

        xpd = New System.Xml.XPath.XPathDocument(ms)
        ms.Close()
        ms = New System.IO.MemoryStream
        xslt.Load(XslFileName)
        xslt.Transform(xpd, Nothing, ms, Nothing)
        xslt = Nothing
        xpn = Nothing
        xpd = Nothing

        sr = New System.IO.StreamReader(ms)
        sr.BaseStream.Seek(0, System.IO.SeekOrigin.Begin)
        rs = sr.ReadToEnd()
        ms.Close()
        sr.Close()
        ms = Nothing
        sr = Nothing
        Return rs
    End Function
End Class