lbl.Text = "";
string test = "##BBB##<html><head></head><body>##AAA##</body></html>";
MatchCollection mc = Regex.Matches(test, @"##/w+##", RegexOptions.IgnoreCase);
string strTemp = "";
foreach (Match m in mc)
{
if (!strTemp.Contains(m.Value))
{
this.lbl.Text += m.Value + "/n";
}
}