How to use background worker to loading a form? c#

Question

How to use background worker in loading a form after clicking a button? I'm gonna use it because my form takes around 20-30secs to load. Please help me.

Answer 1

Here is a sample implementation class from a simple form project. I am using the synchronization context to marshall the progress updates to the UI thread. In the constructor it's getting the context for the current UI thread so it can be used in the background worker thread to provide status updates.

I've also shown you how to cancel a running background worker as well.

public partial class Form1 : Form
{
    BackgroundWorker _worker = new BackgroundWorker();
    SynchronizationContext _syncContext;

    public Form1()
    {
        InitializeComponent();
        _syncContext = SynchronizationContext.Current;
    }

    private void btnLoadForm_Click(object sender, EventArgs e)
    {
        _worker.WorkerReportsProgress = true;
        _worker.WorkerSupportsCancellation = true;
        _worker.DoWork += new DoWorkEventHandler(HandleDoWork);
        _worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(HandleWorkerCompleted);
        _worker.ProgressChanged += new ProgressChangedEventHandler(HandleProgressChanged);
        _worker.RunWorkerAsync();
    }

    private void btnCancel_Click(object sender, EventArgs e)
    {
        if (_worker.WorkerSupportsCancellation)
        {
            _worker.CancelAsync();
        }
    }

    private void HandleDoWork(object sender, DoWorkEventArgs e)
    {
        // DO Any work to instantiate the form
        System.Threading.Thread.Sleep(2000);

        if (_worker.CancellationPending)
        {
            e.Cancel = true;
        }
        else
        {
            Form2 newForm = new Form2();
            newForm.ShowDialog();
        }
    }

    private void HandleProgressChanged(object sender, ProgressChangedEventArgs e)
    {
        // DO Progress Bar Updates Here
        SendOrPostCallback callback = new SendOrPostCallback((o) =>
        {
            label1.Text = "This is my Async content";
        });
        _syncContext.Send(callback, null);
    }

    private void HandleWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        // DO Any completed step items here
    }

}