Question

In this code I am checking all the files from folder root and add only the relevant file into my Listbox.I want an option which marks the last item in my Listbox every iteration.

I think it should be with this command: listBoxFiles.SetSelected(listBoxFiles.Items.Count, true); but if I put this after every time I am add item to my Listbox ArgumentOutOfRange error received.

private void btnAddDir_Click_1(object sender, EventArgs e)
{
    int totalCount = 0;
    int count = 0;
    string fileToAdd = string.Empty;
    List<string> filesList = new List<string>();
    BackgroundWorker backgroundWorker = null;
    DialogResult dialog = folderBrowserDialog1.ShowDialog();
    if (dialog == DialogResult.OK)
    {
        btnAddfiles.Enabled = false;
        btnAddDir.Enabled = false;
        btnPlay.Enabled = false;
        Editcap editcap = new Editcap();

        foreach (string file in SafeFileEnumerator.EnumerateFiles(folderBrowserDialog1.SelectedPath, "*.*", SearchOption.AllDirectories))
        {
            if (editcap.isWiresharkFormat(file))
            {
                filesList.Add(file);
                totalCount++;
            }
        }

        backgroundWorker = new BackgroundWorker();
        backgroundWorker.WorkerReportsProgress = true;
        backgroundWorker.DoWork +=
            (s1, e1) =>
            {
                foreach (string fileName in filesList)
                {
                    if (editcap.isWiresharkFormat(fileName))
                    {
                        if (editcap.isLibpcapFormat(fileName))
                        {
                            backgroundWorker.ReportProgress(0, fileName);
                            count++;
                        }
                        else if (!editcap.isLibpcapFormat(fileName))
                        {
                            fileToAdd = editcap.getNewFileName(fileName);
                            backgroundWorker.ReportProgress(0, fileToAdd);                                    
                            count++;
                        }

                        this.Invoke((MethodInvoker)delegate
                        {
                            labelStatus.Text = string.Format("Please wait..({0}/{1} files added)", count, totalCount);
                        });
                    }
                }
            };

        backgroundWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(
        (s1, e1) =>
        {

        });

        backgroundWorker.ProgressChanged +=
         (s1, arguments) =>
         {
             listBoxFiles.Items.Add(arguments.UserState);
         };

        backgroundWorker.RunWorkerAsync();
    }
}

Answer 1

listBoxFiles.SetSelected(listBoxFiles.Items.Count - 1, true);