Running a method in BackGroundWorker and Showing ProgressBar

soham picture soham · Dec 14, 2012 · Viewed 72.5k times · Source

What I want is when some method is doing some task UI keeps itself active and I want to show the progress of the work in a progress-bar.

I have a method, a BackGroundWorker and a Progressbar. I want to call the method when BackGroundWorker starts running and show the progress. The method contains a loop. So, it can report the progress.

So, what can be done?

private void Form1_Load(object sender, EventArgs e)
{
    // TODO: This line of code loads data into the 'dataSet1.TBLMARKET' table. You can move, or remove it, as needed.
    myBGWorker.WorkerReportsProgress = true;
}

private void myBGWorker_DoWork(object sender, DoWorkEventArgs e)
{
    parseFiles();
}

private void myBGWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    myProgressBar.Value = e.ProgressPercentage;
}

private void myBGWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
    MessageBox.Show("Done");
}

private void parseButton_Click(object sender, EventArgs e)
{
    myBGWorker.RunWorkerAsync();
}

public void parseFiles()
{
  for()
  {
     //parsing
     myBGWorker.ReportProgress(...);
  }
}

But it's not working. The Progressbar is not updating. Only a small progress is showing after the MessageBox "Done".

Answer

Sergey Berezovskiy picture Sergey Berezovskiy · Dec 14, 2012

Instead of using one ParseFiles method (which should depend on myBGWorker) use loop and method which parse one file. Report progress percentage in that loop:

private void parseButton_Click(object sender, EventArgs e)
{
    parseButton.Enabled = false;
    myBGWorker.RunWorkerAsync();
}

private void myBGWorker_DoWork(object sender, DoWorkEventArgs e)
{
   for(int i = 0; i < filesCount; i++)
   {  
       ParseSingleFile(); // pass filename here
       int percentage = (i + 1) * 100 / filesCount;
       myBGWorker.ReportProgress(percentage);
   }
}

void myBGWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    myProgressBar.Value = e.ProgressPercentage;
}

void myBGWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
    parseButton.Enabled = true;
    MessageBox.Show("Done");
}