Reputation: 93
Do I need to synchronize calls to the Dispatcher.Invoke if accessing from multiple background threads?
I know the Dispatcher.BeginInvoke automatically synchronizes calls for silverlight app (http://msdn.microsoft.com/en-us/library/z8chs7ft(v=vs.95).aspx)
Is it also true for a wpf application or should I uncomment the lock statement below.
public MainWindow()
{
InitializeComponent();
Dispatcher.BeginInvoke(new Action(() =>
{
const int MAX_NR_THREADS = 1000;
for (int i = 0; i < MAX_NR_THREADS; ++i)
{
int j = i+1;
new Thread(()=>ThreadMethod(j)).Start();
}
}));
}
private void ThreadMethod(int threadId)
{
const int ONE_MILLION = 1000000;
for (int i = 0; i < ONE_MILLION/threadId; ++i)
{
//lock(lockObj)
//{
this.Dispatcher.Invoke(new Action(() =>
{
int sum = 0;
for (int j = 0; j < ONE_MILLION/10000; ++j)
{
sum += j;
}
int a = sum;
concurrentQueue.Enqueue(threadId*ONE_MILLION);
}));
//}
}
}
Upvotes: 4
Views: 2523
Reputation: 564413
There is no need to synchronize these calls. Dispatcher.Invoke
effectively acts as a queue for your calls already, and doesn't require synchronization.
Upvotes: 6