Multilingual Web Forms Application: Problem with Controls texts

Question

User223078540 posted

I want the users of my web forms application to select the Site language from a DropDownList control.

I am offering two languages: English and Spanish.

I used VS 2010 Web Forms Application template, so I have a Master Page (Site.Master) and two pages (Default.aspx and About.aspx).

In the Session section of the global asax file I created a variable strLanguage.

In SiteMaster I added the DropDownList with 3 Items: "", "English" and "Español".

In the selected index changed event I added the following code:

 If ddlLanguage.SelectedValue <> "" Then
            Session("strLanguage") = ddlLanguage.SelectedValue
            Response.Redirect(Request.Url.LocalPath)
        End If

In my "default" and "about" pages I added code to:

Imports System.Threading
Imports System.Globalization

And, in the load event, added the code

Select Case Session("strLanguage")
            Case "English"
                Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("en")
                Thread.CurrentThread.CurrentUICulture = CultureInfo.CreateSpecificCulture("en")
            Case "Español"
                Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("es")
                Thread.CurrentThread.CurrentUICulture = CultureInfo.CreateSpecificCulture("es")
        End Select

I created two resource files:
 Strings.resx (English strings)
 Strings.es.resx

If I add text in the form

 <%= Resources.Strings.txtLogin%>

It works ok. The string appears in the DropDownList selected language

But, If I try to use a label control and write the following code

<asp:Label ID="Label1" runat="server" Text="<%$ Resources:Strings, txtCL %>"> </asp:Label>

The string is shown always in English.

I checked the string key and it is correct: txtCL.

I tried with the string txtLogin and it works as free text, but the label text is always in English.

Any help to solve this?

Is this the best way to develop the multilingual web forms application?

Thank you

Answer 1

User-925286913 posted

You need to set culture in InitializeCulture() event.

Refer:

http://msdn.microsoft.com/en-us/library/bz9tc508.aspx

Answer 2

User223078540 posted

Thank you chintanpshah,

I read the post you pointed out and followed their instructions.

I had two problems with this post:

1. I am using a Master Page and the drop down list is in it. Since master Pages are not pages, but controls, they don't take the Page directive.

2. I wanted to store the selected language in a session variable and session is not available at the time InitializeCulture() is executed.

I found this post: http://forums.asp.net/t/969928.aspx?PageIndex=1 from rmprimo that provides a solution with master pages and global.asax.

I wrote a VB version of rmprimo solution (slightly different):

In Global.asax.vb file:

Imports System.Threading
Imports System.Globalization

Sub Application_BeginRequest(ByVal sender As Object, ByVal e As EventArgs)
        ' Fires at the beginning of each request
        Dim lang As String = String.Empty 'default to the invariant culture
        Dim cookie As HttpCookie = Request.Cookies("SelectedLanguage")
        If Not IsNothing(cookie) Then
            lang = cookie.Value
            Thread.CurrentThread.CurrentUICulture = CultureInfo.GetCultureInfo(lang)
            Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(lang)
        End If
End Sub 

In the master page:

<asp:DropDownList ID="ddlLanguage" runat="server" AutoPostBack="True">
          <asp:ListItem></asp:ListItem>
          <asp:ListItem Value="en">English</asp:ListItem>
          <asp:ListItem Value="es">Español</asp:ListItem>
</asp:DropDownList>

The selected index changed handler:

Protected Sub ddlLanguage_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles ddlLanguage.SelectedIndexChanged
        If ddlLanguage.SelectedValue <> "" Then
            Dim cookie As New HttpCookie("SelectedLanguage")
            cookie.Value = ddlLanguage.SelectedValue
            cookie.Expires = Now.AddDays(1)
            Response.SetCookie(cookie)
            Response.Redirect(Request.Url.LocalPath)
        End If
End Sub

 

The only differences are:

1. I store in the cookie the drop down list selected value, instead of its UniqueID.

2. I set the cookie expiration day to 24 hours from the moment it is created / Updated.

 

danludwig, one of the commenters for rmprimo post, is showing a solution using a session variable instead of cookies (http://forums.asp.net/t/969928.aspx?PageIndex=2). Altough I haven't tested it, it looks fine to me.

Thak you again,

Answer 3

User-925286913 posted

I personally use Coockies to store user selected language so that we can restore it on futures user sessions.

I also have settings section in my Admin Panel, where admin can select default language of website. If coockie is not found, I am using language set by administrator.

Answer 4

User223078540 posted

I was told it is bad taste to use cookies in a public application, so I tried danludwig's cookieless solution (http://forums.asp.net/t/969928.aspx?PageIndex=2) and it worked.

With this code, the application opens in IE preferred language (Internet Options-General-Languages) and if the user selects a language from the dropdown control in Site.Master it changes to the selected language.

Note that here we only change uiculture (the user interface) and not culture (date, money, and numbers formats).

The Visual Basic code I am using is: 

'In Site.Master
<asp:DropDownList ID="ddlLanguage" runat="server" AutoPostBack="True" OnSelectedIndexChanged="ddlLanguage_SelectedIndexChanged" OnPreRender="ddlLanguage_PreRender">
     <asp:ListItem Value="en">English</asp:ListItem>
     <asp:ListItem Value="es" selected="True">Español</asp:ListItem>
</asp:DropDownList>

'In Site.Master.vb
Protected Sub ddlLanguage_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles ddlLanguage.PreRender
        Dim ddl As DropDownList = sender
        ddl.SelectedValue = CultureInfo.CurrentUICulture.TwoLetterISOLanguageName
End Sub

Protected Sub ddlLanguage_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles ddlLanguage.SelectedIndexChanged
    Dim ddl As DropDownList = sender
    Session("SelectedLanguage") = ddl.SelectedValue
    Response.Redirect(Page.AppRelativeVirtualPath, True) 'No query string
End Sub

'In Global.asax
Private Sub Global_asax_PreRequestHandlerExecute(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.PreRequestHandlerExecute
    If Not IsNothing(Context.Session) AndAlso Not IsNothing(Context.Session("SelectedLanguage")) Then
        Dim SelectedLanguage As String = Context.Session("SelectedLanguage").ToString().ToLower()
        Dim CurrentLanguage As String = CultureInfo.CurrentUICulture.TwoLetterISOLanguageName.ToLower()
        If Not CurrentLanguage.Equals(SelectedLanguage) Then Thread.CurrentThread.CurrentUICulture = New CultureInfo(Session("selectedLanguage").ToString)
    End If
End Sub

'In Web.Config, inside <system.web>
<globalization culture="auto" uiCulture="auto" />

Answer 5

User-925286913 posted

Will above code retain user selected language for future?

Answer 6

User223078540 posted

It won't. Every time you open the application the language will revert to the browser preferred language.