soapheaderauthentication.asmx

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<%@ WebService Language="VB" Class="SecureWebService" %>

Imports System
Imports System.Web.Services
Imports System.Web.Services.Protocols

Public Class Authentication : Inherits SoapHeader
  Public User As String
  Public Password As String
End Class

Public Class SecureWebService : Inherits WebService
  Public authentication As Authentication

  <WebMethod> _
  <SoapHeader("authentication")> _ 
  Public Function ValidUser() As String
    If User.IsInRole("Customer") Then
      Return "User is in the Customer role..."
    Else If User.Identity.IsAuthenticated Then
      Return "User is valid..."
    Else 
      Return "Not authenticated"
    End If
  End Function
End Class