.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。听起来他们将当前的文化更新为我可以使用的东西。

对于面向 .NET Framework 4.6 及更高版本的应用， CultureInfo.CurrentCulture 和 CultureInfo.CurrentUICulture 被存储 在一个线程的 ExecutionContext 中，它流经异步 操作。 （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

但是为什么 2a 返回 en-US 而不是 de-DE？是因为executionContext不同吗？如果是这样，我怎样才能保持在相同的执行上下文中？

Answer 1

CurrentCulture 和 CurrentUICulture 是独立的属性。您只设置了CurrentCulture，并且您在报告CurrentUICulture 的2a 处除了。如果您在整个代码中始终如一地使用相同的属性（任何一个属性都应该没问题），它会给您预期的结果。