I'm doing it in some sites with ASP.net Routing.
Here is the code:
Sub Application_Start(ByVal sender As Object, ByVal e As EventArgs)
' Code that runs on application startup
RegisterRoutes(RouteTable.Routes)
End Sub
Public Sub RegisterRoutes(ByVal routes As RouteCollection)
Dim reportRoute As Route
Dim DefaultLang As String = "es"
reportRoute = New Route("{lang}/{page}", New LangRouteHandler)
'* if you want, you can contrain the values
'reportRoute.Constraints = New RouteValueDictionary(New With {.lang = "[a-z]{2}"})
reportRoute.Defaults = New RouteValueDictionary(New With {.lang = DefaultLang, .page = "home"})
routes.Add(reportRoute)
End Sub
Then LangRouteHandler.vb class:
Public Class LangRouteHandler
Implements IRouteHandler
Public Function GetHttpHandler(ByVal requestContext As System.Web.Routing.RequestContext) As System.Web.IHttpHandler _
Implements System.Web.Routing.IRouteHandler.GetHttpHandler
'Fill the context with the route data, just in case some page needs it
For Each value In requestContext.RouteData.Values
HttpContext.Current.Items(value.Key) = value.Value
Next
Dim VirtualPath As String
VirtualPath = "~/" + requestContext.RouteData.Values("page") + ".aspx"
Dim redirectPage As IHttpHandler
redirectPage = BuildManager.CreateInstanceFromVirtualPath(VirtualPath, GetType(Page))
Return redirectPage
End Function
End Class
Finally I use the default.aspx in the root to redirect to the default lang used in the browser list.
Maybe this can be done with the route.Defaults, but don't work inside Visual Studio (maybe it works in the server)
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
Dim DefaultLang As String = "es"
Dim SupportedLangs As String() = {"en", "es"}
Dim BrowserLang As String = Mid(Request.UserLanguages(0).ToString(), 1, 2).ToLower
If SupportedLangs.Contains(BrowserLang) Then DefaultLang = BrowserLang
Response.Redirect(DefaultLang + "/")
End Sub
Some sources:
* Mike Ormond's blog
* Chris Cavanagh’s Blog
* MSDN