Redirection Based on Accept-Language Using ASP

ID: Q208935

The information in this article applies to:

Microsoft Internet Information Server versions 4.0, 5.0

SUMMARY

When you run a multi-language site, you may want to redirect Web browsers to a directory containing content based on the language that is accepted by the Web browser.

MORE INFORMATION

When a Web browser makes a request to a Web server, it sends an HTTP request that may look similar to the following:


   Accept: application/vnd.ms-excel, */*
   Accept-Language: en-us,ru;q=0.5
   Connection: Keep-Alive
   Host: www.microsoft.com
   Referer: <LINK TYPE="GENERIC" VALUE="http://www.microsoft.com/">http://www.microsoft.com/</LINK>
   User-Agent: Mozilla/4.0 (compatible; MSIE 4.01; Windows 98)
   Accept-Encoding: gzip, deflate

By testing for the Accept-Language value using Active Server Pages (ASP), a browser can be sent to a directory based on that value. The ASP code below detects the first accepted language code and redirects the Web browser to a folder with the same name as the accept language, or it does nothing if it is the default language for your site.

Copy the following code, paste it into Notepad, and then save the file as "Langrdr.inc" (without the quotation marks) into the root of your Web site:


      <%
     Dim strURL,strACCEPT
     strACCEPT = GetAcceptLanguage()

     ' change the language code below to customize the default
     If strACCEPT <> "en-us" Then
       strURL = "http://" & Request.ServerVariables("HTTP_HOST")
       strURL = strURL & "/" & strACCEPT & "/"
       Response.Redirect strURL
     End If

     ' this function returns the first accept-language
     Function GetAcceptLanguage()
       Dim strHTTP, strLANG, strTEMP, intTEMP
       strHTTP = LCase(Request.ServerVariables("ALL_RAW"))
       If InStr(strHTTP,"accept-language:") Then
         strHTTP = Trim(Mid(strHTTP,16+InStr(strHTTP,"accept-language:")))
         For intTEMP = 1 to Len(strHTTP)
           strTEMP = Mid(strHTTP,intTEMP,1)
           If IsAlpha(strTEMP) Or strTEMP = "-" Then
             strLANG = strLANG & strTEMP
           Else
             GetAcceptLanguage = strLANG
             Exit Function
           End If
         Next    
       End If
     End Function

     ' determine if the character passed is a letter
     Function IsAlpha(strCHAR)
       If (Asc(strCHAR)>=65 And Asc(strCHAR)<=90) Or _
         (Asc(strCHAR)>=97 And Asc(strCHAR)<=122) Then
         IsAlpha = -1
       Else
         IsAlpha = 0
       End If
     End Function
   %>

Copy the following two lines of code to the top of your Web site's Default.asp page:
```
   <%@LANGUAGE="VBSCRIPT"%>
    
```

The above code may look similar to the following when used in a Web page:


<%@LANGUAGE="VBSCRIPT"%>
   <!--#include virtual="/langrdr.inc"-->
   <html>
   <head><title>Welcome</title></head>
   <body>
   <h1>Welcome to my page!</h1>
   </body>
   </html>

Add directories or virtual directories based on language codes. For example:


   de = German, c:\inetpub\wwwroot\de
   es = Spanish, c:\inetpub\wwwroot\es
   fr = French, c:\inetpub\wwwroot\fr
   ru = Russian, c:\inetpub\wwwroot\ru

For more information on the Accept-Language header and the currently-defined language codes, please see the following URLs:

ftp://ftp.isi.edu/in-notes/rfc1766.txt
http://www.dsv.su.se/~jpalme/ietf/language-codes.html
http://www.sci.usq.edu.au/staff/vance/iso639/

Additional query words:


Keywords          : 
Version           : winnt:4.0,5.0
Platform          : winnt 
Issue type        : kbhowto

Last Reviewed: February 4, 1999