.net-4.6中的异步Thread.CurrentThread.CurrentCulture

Question

由于以下来自微软的信息，我稍微更新了我的代码。听起来他们把现在的文化更新到我可以用的东西了。

对于针对.NET Framework4.6及更高版本的应用程序，CultureInfo.CurrentCulture和CultureInfo.CurrentUICulture存储在线程的ExecutionContext中，后者跨异步操作流动。(资料来源：https://msdn.microsoft.com/en-us/library/dn833123(v=vs.110).aspx

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

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("start " + Thread.CurrentThread.CurrentCulture.ToString() + " " + Thread.CurrentThread.ManagedThreadId);
        RunAsync().Wait();
        Console.WriteLine("Finish " + Thread.CurrentThread.CurrentCulture.ToString() + " " + Thread.CurrentThread.ManagedThreadId);
        Console.ReadKey();
    }

    static async Task RunAsync()
    {
        Thread.CurrentThread.CurrentCulture = new System.Globalization.CultureInfo("de-DE");

        Console.WriteLine("1 " + Thread.CurrentThread.CurrentCulture.ToString() + " " + Thread.CurrentThread.ManagedThreadId);
        string cultureInTask = string.Empty;

        await Task.Run(() => cultureInTask = Thread.CurrentThread.CurrentCulture.ToString() + " " + Thread.CurrentThread.ManagedThreadId).ConfigureAwait(true);

        Console.WriteLine("2 " + cultureInTask);
        string twoA = await TestMethodAsync();
        Console.WriteLine("2a " + twoA + " " + Thread.CurrentThread.ManagedThreadId);
        Console.WriteLine("3 " + Thread.CurrentThread.CurrentCulture.ToString() + " " + Thread.CurrentThread.ManagedThreadId);            
    }

    public static async Task<string> TestMethodAsync()
    {
        Console.WriteLine("2s " + Thread.CurrentThread.CurrentCulture.ToString() + " " + Thread.CurrentThread.ManagedThreadId);
        return await Task.Run(() =>
        {
            return System.Threading.Thread.CurrentThread.CurrentUICulture.ToString() + " " + Thread.CurrentThread.ManagedThreadId;
        });
    }
}

输出：

start en-US 1
1 de-DE 1
2 de-DE 3
2s de-DE 3
2a en-US 4 4
3 de-DE 4
Finish en-US 1

但为什么2a会返回美国而不是DE？是因为executionContext不一样吗？如果是这样，我如何才能保持在相同的执行上下文中？

Answer 1

CurrentCulture和CurrentUICulture是两个独立的属性。您只是在设置CurrentCulture，并且在任何地方都报告，除了2a，它报告CurrentUICulture。如果在整个代码中始终使用相同的属性(这两个属性都应该可以)，它将给出预期的结果。