DefaultCurrentCultureExample.cs

using System;
using System.Globalization;
using System.Reflection;
using System.Threading;
 
namespace DefaultCultureInfoExample
{
    class Program
    {
        static void SetDefaultCulture(CultureInfo culture)
        {
            Type type = typeof(CultureInfo);
 
            try
            {
                type.InvokeMember("s_userDefaultCulture",
                                    BindingFlags.SetField | BindingFlags.NonPublic | BindingFlags.Static,
                                    null,
                                    culture,
                                    new object[] { culture });
 
                type.InvokeMember("s_userDefaultUICulture",
                                    BindingFlags.SetField | BindingFlags.NonPublic | BindingFlags.Static,
                                    null,
                                    culture,
                                    new object[] { culture });
            }
            catch { }
 
            try
            {
                type.InvokeMember("m_userDefaultCulture",
                                    BindingFlags.SetField | BindingFlags.NonPublic | BindingFlags.Static,
                                    null,
                                    culture,
                                    new object[] { culture });
 
                type.InvokeMember("m_userDefaultUICulture",
                                    BindingFlags.SetField | BindingFlags.NonPublic | BindingFlags.Static,
                                    null,
                                    culture,
                                    new object[] { culture });
            }
            catch { }
        }
 
        static void Main(string[] args)
        {
            Console.WriteLine("Culture name before update: {0}", 
                              Thread.CurrentThread.CurrentCulture.Name);
 
            SetDefaultCulture(new CultureInfo("fr-fr"));
            Console.WriteLine("Culture name after update: {0}", 
                              Thread.CurrentThread.CurrentCulture.Name);
 
            Console.ReadLine();
        }
    }
}