public IEnumerable<string> GetFiles(string directory, string searchPattern)
{
if (String.IsNullOrEmpty(directory))
{
directory = Directory.GetCurrentDirectory();
}
DirectoryInfo directoryInfo = new DirectoryInfo(directory);
FileInfo[] files = directoryInfo.GetFiles(searchPattern, SearchOption.AllDirectories);
foreach (FileInfo file in files)
{
yield return file.FullName;
}
}