这样可以确保该字段在任何时间呈现的都是最新的值。
lock 语句对访问进行序列化的字段。
volatile 关键字可应用于以下类型的字段:
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引用类型。
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换句话说,您无法声明“指向可变对象的指针”。
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类型,如 sbyte、byte、short、ushort、int、uint、char、float 和 bool。
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具有以下基类型之一的枚举类型:byte、sbyte、short、ushort、int 或 uint。
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已知为引用类型的泛型类型参数。
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UIntPtr。
volatile。
volatile。
线程处理(C# 和 Visual Basic)。
using System; using System.Threading; public class Worker { // This method is called when the thread is started. public void DoWork() { while (!_shouldStop) { Console.WriteLine("Worker thread: working..."); } Console.WriteLine("Worker thread: terminating gracefully."); } public void RequestStop() { _shouldStop = true; } // Keyword volatile is used as a hint to the compiler that this data // member is accessed by multiple threads. private volatile bool _shouldStop; } public class WorkerThreadExample { static void Main() { // Create the worker thread object. This does not start the thread. Worker workerObject = new Worker(); Thread workerThread = new Thread(workerObject.DoWork); // Start the worker thread. workerThread.Start(); Console.WriteLine("Main thread: starting worker thread..."); // Loop until the worker thread activates. while (!workerThread.IsAlive) ; // Put the main thread to sleep for 1 millisecond to // allow the worker thread to do some work. Thread.Sleep(1); // Request that the worker thread stop itself. workerObject.RequestStop(); // Use the Thread.Join method to block the current thread // until the object's thread terminates. workerThread.Join(); Console.WriteLine("Main thread: worker thread has terminated."); } // Sample output: // Main thread: starting worker thread... // Worker thread: working... // Worker thread: working... // Worker thread: working... // Worker thread: working... // Worker thread: working... // Worker thread: working... // Worker thread: terminating gracefully. // Main thread: worker thread has terminated. }