Question

I have a console application that utilizes the BackgroundWorker object and wanted to test my output with a Console.WriteLine(fooBar). However, that application exits as the application executes the Console.WriteLine command.

Here’s a watered down version that illustrates what I wanted to do:

protected static void bWorker_DoWork(object sender, DoWorkEventArgs e)
{
    for (int i = startId; i <= endId; i++)
    {
        Console.WriteLine(i.ToString());
        Thread.Sleep(1000);
    }
}

Any ideas why the application would appear to exit like that?

Answer 1

For your backgroundworker set WorkerReportsProgress to true. Subscribe to ProgressChanged event like this:

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
    for (var i = 0; i < 1000; i++)
    {
        backgroundWorker1.ReportProgress(i);
    }
}

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    Console.WriteLine(e.ProgressPercentage);
}

If you need to transfer more than just int from your background thread to UI thread, then you could do something like this:

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
    for (var i = 0; i < 1000; i++)
    {
        var myObjectInstance = new MyObject{ ...};
        backgroundWorker1.ReportProgress(null, myObjectInstance);
    }
}

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    var myObjectInstance = (MyObject)e.UserState;
    Console.WriteLine(myObjectInstance);
}