In WPF, the Invoke method is on the dispatcher, so you need to call Dispatcher.Invoke instead of Invoke. Also, there is no InvokeRequired property, but the dispatcher has a CheckAccess method (for some reason, it’s hidden in intellisense). So your code should be: delegate void ParametrizedMethodInvoker5(int arg); void log_left_accs(int arg) { if (!Dispatcher.CheckAccess()) // CheckAccess … Read more
From non-UI threads we can’t touch the UI – very bad things can happen, since controls have thread affinity. So from a non-UI thread we must (at a minumum) call Invoke or BeginInvoke. For UI-threads, however – we don’t want to call Invoke lots of time; the issue is that if you are already on … Read more
Well how about this: public static class ControlHelpers { public static void InvokeIfRequired<T>(this T control, Action<T> action) where T : ISynchronizeInvoke { if (control.InvokeRequired) { control.Invoke(new Action(() => action(control)), null); } else { action(control); } } } Use it like this: private void UpdateSummary(string text) { summary.InvokeIfRequired(s => { s.Text = text }); }
Lee’s approach can be simplified further public static void InvokeIfRequired(this Control control, MethodInvoker action) { // See Update 2 for edits Mike de Klerk suggests to insert here. if (control.InvokeRequired) { control.Invoke(action); } else { action(); } } And can be called like this richEditControl1.InvokeIfRequired(() => { // Do anything you want with the control … Read more