Write a standard lock plus double check to create a critical section around a variable access?

Answer 1

using System; using System.Text; using System.Threading; namespace thread01 { public class Counter { private int _count=0; private int _even=0; public int Count { get { return _count; } } public int EvenCount { get { return _even; } } private Object theLock = new Object(); public void UpdateCount() { lock (theLock) { _count = _count + 1; if (Count % 2 == 0) // An even number { _even += 1; } } } } class Program { static void Main(string[] args) { Counter count = new Counter(); ParameterizedThreadStart starter = new ParameterizedThreadStart(Program.UpdateCount); Thread[] threads = new Thread[10]; for (int x = 0; x < 10; ++x) { threads[x] = new Thread(starter); threads[x].Start(count); } for (int y = 0; y < 10; ++y) { threads[y].Join(); } Console.WriteLine("Total: {0} - Even: {1}", count.Count,count.EvenCount); Console.ReadKey(); Console.ReadKey(); } static void UpdateCount(object param) { Counter count = (Counter)param; for (int z = 1; z