c# - 使用 DateTime.ToString ("tt"时，Windows 10 中的时间输出(AM/PM)发生了变化)

Question

我最近升级到 Windows 10 - 现在我发现在使用“tt”格式说明符时日期的输出发生了一些意想不到的变化。

下面是一些演示问题的代码:

using System.IO;
using System;
using System.Globalization;
using System.Threading.Tasks;

class Program
{
    static void Main()
    {
        var cultures = new string[] {null, "en-NZ", "en-US", "en-AU", "en-GB"};

            foreach (var culture in cultures) {
                if (culture != null) {
                    var c = CultureInfo.GetCultureInfo(culture);
                    System.Threading.Thread.CurrentThread.CurrentCulture = System.Threading.Thread.CurrentThread.CurrentUICulture = c;
                }

                DateTime dt = new DateTime(2015, 1, 2, 3, 4, 5, DateTimeKind.Utc);

                Console.WriteLine("selection: {0} CurrentThread.CurrentCulture.Name: {1} CurrentThread.CurrentUICulture.Name: {2}  Value: {3}",
                    culture ?? "ambient",
                    System.Threading.Thread.CurrentThread.CurrentCulture.Name,
                    System.Threading.Thread.CurrentThread.CurrentUICulture.Name,
                    dt.ToString("hhh:mm tt"));
            }
    }
}

以前版本的 windows 中的输出是:

selection: ambient CurrentThread.CurrentCulture.Name: en-NZ CurrentThread.CurrentUICulture.Name: en-NZ Value: 03:04 a.m.
selection: en-NZ CurrentThread.CurrentCulture.Name: en-NZ CurrentThread.CurrentUICulture.Name: en-NZ Value: 03:04 a.m.
selection: en-US CurrentThread.CurrentCulture.Name: en-US CurrentThread.CurrentUICulture.Name: en-US Value: 03:04 AM
selection: en-AU CurrentThread.CurrentCulture.Name: en-AU CurrentThread.CurrentUICulture.Name: en-AU Value: 03:04 AM
selection: en-GB CurrentThread.CurrentCulture.Name: en-GB CurrentThread.CurrentUICulture.Name: en-GB Value: 03:04 am

在 Windows 10 中:

selection: ambient (windows 10) CurrentThread.CurrentCulture.Name: en-NZ CurrentThread.CurrentUICulture.Name: en-US  Value: 03:04 a.m.
selection: en-NZ CurrentThread.CurrentCulture.Name: en-NZ CurrentThread.CurrentUICulture.Name: en-NZ  Value: 03:04 AM
selection: en-US CurrentThread.CurrentCulture.Name: en-US CurrentThread.CurrentUICulture.Name: en-US  Value: 03:04 AM
selection: en-AU CurrentThread.CurrentCulture.Name: en-AU CurrentThread.CurrentUICulture.Name: en-AU  Value: 03:04 AM
selection: en-GB CurrentThread.CurrentCulture.Name: en-GB CurrentThread.CurrentUICulture.Name: en-GB  Value: 03:04 AM

在这两种情况下，这段代码都是针对 .Net Framework 4.5 在 Visual Studio 2013 中编译的

有谁知道行为发生变化的原因 - 以及为什么在 Windows 10 中似乎在线程上设置任何区域性会专门更改 AM/PM 的输出以格式化为“AM”/“PM”，而不是通常输出的内容那种文化？

Answer 1

您可能需要查看“文化数据不应该被认为是稳定的”http://blogs.msdn.com/b/shawnste/archive/2005/04/05/405694.aspx

一点是，我们开始为许多语言环境利用 CLDR(通用语言环境数据存储库，http://cldr.unicode.org)，以更好地与行业标准保持一致。您可能已经注意到，我们现在有很多其他语言环境的数据。