ThreadStaticAttribute和ThreadLocal使用区别总结

ThreadStaticAttribute和ThreadLocal<T>都是提供线程本地存储，ThreadLocal<T>是.net4才提供的。

ThreadStaticAttribute只能标注静态字段，而ThreadLocal<T>可以对实例字段才有效。

如果不标注ThreadStaticAttribute，则多个线程共享一个变量，这样的话会引起冲突的。

 class Program
    {
          static void Main()
        {
             Console.WriteLine("use [ThreadStaticAttribute]");
            for (int i = 0; i < 3; i++)
            {
                Thread newThread = new Thread(ThreadData1.ThreadStaticDemo);
                newThread.Start();
            }
 
            Thread.Sleep(500);
            Console.WriteLine("not use [ThreadStaticAttribute]");
            for (int i = 0; i < 3; i++)
            {
                Thread newThread = new Thread(ThreadData2.ThreadStaticDemo);
                newThread.Start();
            }
             Thread.Sleep(500);
            Console.WriteLine("not use static member, use instance member");
            for (int i = 0; i < 3; i++)
            {
                Thread newThread = new Thread((new ThreadData3()).ThreadStaticDemo);
                newThread.Start();
            }
             Thread.Sleep(500);
            Console.WriteLine("");
            for (int i = 0; i < 3; i++)
            {
                Thread newThread = new Thread(ThreadData4.ThreadStaticDemo);
                newThread.Start();
            }
              Thread.Sleep(500);
            Console.WriteLine("not use [ThreadStaticAttribute], use ThreadLocal<int>");
            for (int i = 0; i < 3; i++)
            {
                Thread newThread = new Thread(ThreadData5.ThreadStaticDemo);
                newThread.Start();
            }
             Thread.Sleep(500);
            Console.WriteLine("not use [ThreadStaticAttribute], use ThreadLocal<int>");
              ThreadLocal<string> ThreadName = new ThreadLocal<string>(() =>
            {
                return "Thread" + Thread.CurrentThread.ManagedThreadId;
            });
 
            // Action that prints out ThreadName for the current thread
            Action action = () =>
            {
                // If ThreadName.IsValueCreated is true, it means that we are not the
                // first action to run on this thread.
                bool repeat = ThreadName.IsValueCreated;
 
                Console.WriteLine("ThreadName = {0} {1}", ThreadName.Value, repeat ? "(repeat)" : "");
            };
 
            // Launch eight of them.  On 4 cores or less, you should see some repeat ThreadNames
            Parallel.Invoke(action, action, action, action, action, action, action, action);
              // Dispose when you are done
            ThreadName.Dispose();
          }
      }
 
    class ThreadData1
    {
        static int threadSpecificData;
        public static void ThreadStaticDemo()
        {
            // Store the managed thread id for each thread in the static
            // variable.
            threadSpecificData = Thread.CurrentThread.ManagedThreadId;
 
            // Allow other threads time to execute the same code, to show
            // that the static data is unique to each thread.
            Thread.Sleep(100);
 
            // Display the static data.
            Console.WriteLine("Data for managed thread {0}: {1}",
                Thread.CurrentThread.ManagedThreadId, threadSpecificData);
 
        }
    }
 
    class ThreadData2
    {
        [ThreadStaticAttribute]//可¨¦以°?省º?去¨£¤Attribute直¡À接¨®写¡ä[ThreadStatic] 语®?法¤¡§糖¬?
        static int threadSpecificData;
        public static void ThreadStaticDemo()
        {
            // Store the managed thread id for each thread in the static
            // variable.
            threadSpecificData = Thread.CurrentThread.ManagedThreadId;
 
            // Allow other threads time to execute the same code, to show
            // that the static data is unique to each thread.
            Thread.Sleep(100);
 
            // Display the static data.
            Console.WriteLine("Data for managed thread {0}: {1}",
                Thread.CurrentThread.ManagedThreadId, threadSpecificData);
 
        }
    }
 
    class ThreadData3 //使º1用®?实º¦Ì例¤y方¤?法¤¡§也°2可¨¦以°?实º¦Ì现?上¦?述º?效¡ì果?，ê?每?个?线?程¨¬单Ì£¤独¨¤使º1用®?各¡Â自Á?的Ì?变À?量¢?
    {
        int threadSpecificData;
 
        public void ThreadStaticDemo()
        {
            // Store the managed thread id for each thread in the static
            // variable.
            threadSpecificData = Thread.CurrentThread.ManagedThreadId;
 
            // Allow other threads time to execute the same code, to show
            // that the static data is unique to each thread.
            Thread.Sleep(100);
 
            // Display the static data.
            Console.WriteLine("Data for managed thread {0}: {1}",
                Thread.CurrentThread.ManagedThreadId, threadSpecificData);
          }
    }
      class ThreadData4
    {
        [ThreadStaticAttribute]//可¨¦以°?省º?去¨£¤Attribute直¡À接¨®写¡ä[ThreadStatic] 语®?法¤¡§糖¬?
        static test t = null;
        public static void ThreadStaticDemo()
        {
            t = new test();
 
            Thread.Sleep(100);
            // Display the static data.
            Console.WriteLine(t.testvalue);
 
        }
    }
      class test
    {
        public int testvalue = 0;
          public test()
        {
            testvalue++;
        }
    }
 
 
    class ThreadData5
    {
        static ThreadLocal<int> threadSpecificData = new ThreadLocal<int>();//only in .net framework 4.0. no need to use [ThreadStaticAttribute]
         static public void ThreadStaticDemo()
        {
            // Store the managed thread id for each thread in the static
            // variable.
            threadSpecificData.Value = Thread.CurrentThread.ManagedThreadId;
              // Allow other threads time to execute the same code, to show
            // that the static data is unique to each thread.
            Thread.Sleep(100);
 
            // Display the static data.
            Console.WriteLine("Data for managed thread {0}: {1}",
                Thread.CurrentThread.ManagedThreadId, threadSpecificData.Value);
          }
    }