global.asax

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<%@ Import Namespace="System.Xml" %>

<Script language="VB" runat="server">

  Public Sub Application_OnAcquireRequestState(sender As Object, e As EventArgs)
    Dim dom As New XmlDocument()
    Dim customerType As String

    ' Grab the customerType from the QueryString
    customerType = Request.QueryString("customerType")

    ' Check for values
    If (IsNothing(customerType))
      customerType = "Bronze"
    End If

    ' Load the appropriate XML file
    Select Case customerType
      Case "Gold"
        dom.Load(Server.MapPath("Gold.xml"))
      Case "Silver"
        dom.Load(Server.MapPath("Silver.xml"))
      Case Else
        dom.Load(Server.MapPath("Bronze.xml"))
    End Select

    Session("WelcomeMsg") = dom.SelectSingleNode("/customer/welcome").InnerText
  End Sub</Script>