c# - How do I update a Label from within a BackgroundWorker thread?

Question

When I used WinForms, I would have done this in my bg_DoWork method:

status.Invoke(new Action(() => { status.Content = e.ToString(); }));
status.Invoke(new Action(() => { status.Refresh(); }));

However in my WPF application I get an error saying that Invoke does not exist for Label.

Any help would be appreciated.

Answer 1

Use the capabilities already built into the BackgroundWorker. When you "report progress", it sends your data to the ProgressChanged event, which runs on the UI thread. No need to call Invoke().

private void bgWorker_DoWork(object sender, DoWorkEventArgs e)
{
    bgWorker.ReportProgress(0, "Some message to display.");
}

private void bgWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    status.Content = e.UserState.ToString();
}

Make sure you set bgWorker.WorkerReportsProgress = true to enable reporting progress.