我想了解ExecutionContext实际上在.NET Framework 4.0及更高版本中的工作原理。该文档指出,在使用Thread.Start和大多数线程池操作时,托管原则,同步,语言环境和用户上下文都将流向新线程。但在实践中我看不到这一点。.NET ExecutionContext如何实际工作?
这里是如果同步内容和管理原则流开始一个新的线程时测试一个简单的控制台应用程序...
static void Main(string[] args)
{
SynchronizationContext.SetSynchronizationContext(new SynchronizationContext());
Thread.CurrentPrincipal = new GenericPrincipal(new GenericIdentity("One"), null);
Thread t1 = new Thread(new ThreadStart(ThreadRun));
t1.Start();
t1.Join();
SynchronizationContext.SetSynchronizationContext(new SynchronizationContext());
Thread.CurrentPrincipal = new GenericPrincipal(new GenericIdentity("Two"), null);
AsyncFlowControl aFC = ExecutionContext.SuppressFlow();
Thread t2 = new Thread(new ThreadStart(ThreadRun));
t2.Start();
t2.Join();
aFC.Undo();
Console.Read();
}
static void ThreadRun()
{
Console.WriteLine("ThreadRun Id={0} Context={1} Principle={2}",
Thread.CurrentThread.ManagedThreadId,
(SynchronizationContext.Current != null),
Thread.CurrentPrincipal.Identity.Name);
}
结果是...
ThreadRun Id=11 Context=False Principle=One
ThreadRun Id=12 Context=False Principle=Two
所以同步上下文永远不会流动,即使您指定它不应该,托管原则也会始终流动。基本上文件是完全错误的。那么是否有对ExecutionContext在现实中做什么的描述以及它为什么有用?