private void Calculate(int i){ double pow = Math.Pow(i, i);}private void button1_Click(object sender, EventArgs e){ progressBar1.Maximum = 100; progressBar1.Step = 1; progressBar1.Value = 0; backgroundWorker.RunWorkerAsync();}private void backgroundWorker_DoWork(object sender, DoWorkEventArgs e){ var backgroundWorker = sender as BackgroundWorker; for (int j = 0; j < 100000; j++) { Calculate(j); backgroundWorker.ReportProgress((j * 100) / 100000); }}private void backgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e){ progressBar1.Value = e.ProgressPercentage;}private void backgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e){ // TODO: do something with final calculation.}