GUI Windows Form C#

using System.IO;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Text.RegularExpressions;
public class Utils
{
    public static List GetFilesFromFolder(bool bSubDirs)
    {
        FolderBrowserDialog dlgFolder = new FolderBrowserDialog();
        dlgFolder.SelectedPath = "";
        if (dlgFolder.ShowDialog() == DialogResult.Cancel)
            return new List();
        string sDir = dlgFolder.SelectedPath;
        string[] sFileList;
        if (bSubDirs)
            sFileList = Directory.GetFiles(sDir, "*.*", SearchOption.AllDirectories);
        else
            sFileList = Directory.GetFiles(sDir);
        return new List(sFileList);
    }
}