线程池是一种多线程处理形式，处理过程中将任务添加到队列，然后在创建线程后自动启动这些任务。线程池线程都是后台线程.每个线程都使用默认的堆栈大小,以默认的优先级运行,并处于多线程单元中.如果某个线程在托管代码中空闲(如正在等待某个事件),则线程池将插入另一个辅助线程来使所有处理器保持繁忙.如果所有线程池线程都始终保持繁忙,但队列中包含挂起的工作,则线程池将在一段时间后创建另一个辅助线程但线程的数目永远不会超过最大值.超过最大值的线程可以排队,但他们要等到其他线程完成后才启动-Thread pooling is a form of multi-threaded processing, processing tasks will be added to the queue, and then create a thread automatically start these tasks. Thread pool threads are background threads. Each thread uses the default stack size to run the default priority, and in multi-threaded unit. If a thread is idle in managed code (such as waiting for an event), the thread pool of worker threads to be inserted into another to keep all processors busy. if all thread pool threads are always kept busy, but the work queue contains pending, the thread pool will be created after a period of time, but another worker thread The number of threads will never exceed the maximum. more than the maximum thread can queue up, but they have to wait until after the start other threads to complete