更改线程区域性 .NET Framework 4.6 及更高版本

Question

我正在尝试更改一个新线程 CultureInfo，如下面的示例，但是：

• Attempt1：SetCulture1() 没有更改我的线程

• Attempt2: SetCulture2() 我收到异常“System.InvalidOperationException: instance is read-only”（设置 CurrencyDecimalSeparator 时）

  static void Main(string[] args)
  {
      Thread th = new Thread(thread_test);
  
      // nothing happens
      SetCulture1(th);
  
      // exception System.InvalidOperationException: instance is read-only
      SetCulture2(th);
  
      th.Start();
  }
  
  public static void SetCulture1(System.Threading.Thread thread)
  {
      var ci = new System.Globalization.CultureInfo("pt-BR");
      ci.NumberFormat.CurrencyDecimalSeparator = ".";
  
      thread.CurrentCulture = ci; // <-- after this culture info not change
  
      if (thread.CurrentCulture.NumberFormat.CurrencyDecimalSeparator != ".")
      {
          Console.WriteLine("Nothing happened");
          Console.ReadKey();
      }
  }
  
  public static void SetCulture2(System.Threading.Thread thread)
  {
      thread.CurrentCulture = new System.Globalization.CultureInfo("pt-BR");
      thread.CurrentCulture.NumberFormat.CurrencyDecimalSeparator = "."; // <-- exception throws here
  }
  
  static void thread_test()
  {
      Console.WriteLine("Culture: {0}", CultureInfo.CurrentCulture.DisplayName);
  }
  

我注意到，在 .net 4.6 之前，此示例有效。 4.6 有什么变化吗？

谢谢！

Answer 1

虽然这种奇怪的情况没有答案 (Microsoft bug report)，但我找到了一个解决方法，可以在代码开头设置 DefaultThreadCurrentCulture（Main 方法）：

        var ci = new System.Globalization.CultureInfo(System.Globalization.CultureInfo.CurrentCulture.LCID);
        ci.NumberFormat.CurrencyDecimalSeparator = ".";
        ci.NumberFormat.CurrencyGroupSeparator = ",";
        ci.NumberFormat.NumberDecimalSeparator = ".";
        ci.NumberFormat.NumberGroupSeparator = ",";
        ci.NumberFormat.PercentDecimalSeparator = ".";
        ci.NumberFormat.PercentGroupSeparator = ",";
        System.Globalization.CultureInfo.DefaultThreadCurrentCulture = ci;
        System.Globalization.CultureInfo.DefaultThreadCurrentUICulture = ci;