C# 5.0 Programmer's Reference

Chapter 22 ❘ 709
The DeadUnlock example program uses the following code for Task A.
// Task A.
private void TaskA()
{
for (int attempts = 0; attempts < 10; attempts++)
{
Console.WriteLine("TaskA: Locking A");
if (Monitor.TryEnter(LockObjectA))
{
try
{
Thread.Sleep(1);
Console.WriteLine("TaskA: Locking B");
if (Monitor.TryEnter(LockObjectB))
{
try
{
// Update the value.
BestValue = ValueA;
}
}
// We're done. Break out of the retry loop.
Console.WriteLine("Task A: Done");
return;
}
finally
{
Console.WriteLine("Task A: Releasing lock B");
Monitor.Exit(LockObjectB);
}
}
else
{
Console.WriteLine("Task A: Lock B failed");
}
}
finally
{
Console.WriteLine("Task A: Releasing lock A");
Monitor.Exit(LockObjectA);
}
}
else
{
Console.WriteLine("Task A: Lock A failed");
}
The code used by Task B is similar so it isn’t shown here. The only difference is that Task B
tries to lock LockObjectB first and LockObjectA second.
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