Question

I have list of files(widgets) that I need to do some work on. I want to do it in async manner so my interface stays responsive. I want to update UI with progress. Here is my prototype code. How do I accomplish this? I assume I need to utilize threading, but I also don’t want to span all the threads at the same time, one by one is fine.

void Process()
{
    var documents = GetDocuments();
    foreach(document in documents)
    {
        ProcessDocument(
        document,
        status => this.TextBox.Text += status); 
    }
}

void ProcessDocument(Document document, Action<string> onCompleted)
{
}

Answer 1

You can use the BackgroundWorker class to process operation asynchronous in Windows Forms projects.

BackgroundWorker worker = new BackgroundWorker();
worker.WorkerReportsProgress = true;
worker.DoWork += (sender, args) => {
    var documents = GetDocuments();
    foreach(var document in documents)
    {
        ProcessDocument(document);
        worker.ReportProgress(0, status);
    }
};
worker.ProgressChanged += (sender, args) => {
    this.TextBox.Text += args.UserState.ToString();
};
worker.RunWorkerAsync();