Does the saveLedgers() method need to run on the UI thread?

If not then you can do something like:

   public class Test
    {
        public void Doit()
        {
            var bg36 = new BackgroundWorker();
            bg36.DoWork += bg36_DoWork;
            bg36.RunWorkerAsync(this);
        }


        public void SaveLedgers()
        {
        }

        private  void bg36_DoWork(Object sender, DoWorkEventArgs e)
        {
            var t = (Test) e.Argument;
            t.SaveLedgers();
        }

    }

>I'm using Excel interop and it seems that this functionality needs to run in the UI thread.
>So I execute that from the ProgressChanged backgroundworker event.
>Is there a way to have the dowork event (that invoked the progress changed event) interrupt execution until the ProgressChanged event is finished?
>
>Here's how the bg is initialized:
>
>

>       private void initializeBackgroundWorker()
>        {
>            bg36 = new BackgroundWorker();
>            bg36.DoWork += bg36_DoWork;
>            bg36.RunWorkerCompleted += bg36_RunWorkerCompleted;
>            bg36.WorkerReportsProgress = true;
>            bg36.ProgressChanged += bg36_ProgressChanged;
>            bg36.WorkerSupportsCancellation = true;
>        }
>

>
>This is how the process is started:
>
>

>       private void bg36_DoWork(object sender, DoWorkEventArgs e)
>        {
>            BackgroundWorker bw = (BackgroundWorker)sender;
>

>
>This is the call to the UI thread
>
>

>            bw.ReportProgress(0, "save ledgers");
>

>
>And this is the routine I would like to complete before the worker continues
>
>

>       private void bg36_ProgressChanged(object sender, ProgressChangedEventArgs e)
>        {
>            statusTextBlock.Text = (string)e.UserState + "\n\n" + Monitor.peek();
>            if ((string)e.UserState== "save ledgers")
>	        {
>		         saveLedgers();
>            }
>        }
>