An ASP.NET HttpModule to set the current culture to the user’s locale

Update: sandord, in the comments, has pointed out that you can achieve the same result with a simple configuration setting in Web.config:

<globalization culture="auto" uiculture="auto" enableClientBasedCulture="”true”" />

My web application TardisBank (a pocket money bank account for kids) needs to show users the currency symbol for their location. So UK users should see ‘£’, but US users should see ‘$’. I’d thought that I would have to ask the user to choose a currency symbol when they signed up, but Dylan Beattie had a much better idea:

A quick Google turned up this excellent article by Rick Strahl, ‘detecting and setting the current locale on the current asp.net web request’.

Using Rick’s code I quickly created an ASP.NET module:

using System;
using System.Globalization;
using System.Threading;
using System.Web;

namespace Suteki.TardisBank.Mvc
{
    public class UserLocaleModule : IHttpModule
    {
        public void Init(HttpApplication httpApplication)
        {
            httpApplication.BeginRequest += (sender, eventArgs) =>
            {
                var app = sender as HttpApplication;
                if (app == null)
                {
                    throw new ApplicationException("Sender is null or not an HttpApplication");
                }
                var request = app.Context.Request;
                if (request.UserLanguages == null || request.UserLanguages.Length == 0) return;

                var language = request.UserLanguages[0];
                if (language == null) return;

                try
                {
                    Thread.CurrentThread.CurrentCulture = new CultureInfo(language);
                }
                catch
                {}
            };
        }

        public void Dispose()
        {
            
        }
    }
}

Which I configured in TardisBank’s web.config:

<modules runAllManagedModulesForAllRequests="true">
  <add name="UserLocale" type="Suteki.TardisBank.Mvc.UserLocaleModule, Suteki.TardisBank" />
</modules>

And now I’ve got currency symbols :)

And if I change my browser’s language settings:

I now get the $ symbol instead:

Thanks Dylan & Rick! It’s a very neat solution.