int x, resi,a; x = int.Parse(txtNum.Text); resi = x; string r; r = ""; for (a = 0; x > 0; a ++) { resi = x % 2; r = resi.ToString() + r; x = x / 2; } lblResul.Text = r;rogrmam

You can use the following code to get the result you want:
string html = @"<table><tr><td>1</td><td>2</td></tr><tr><td>3</td><td>4</td></tr></table>";
string pattern = @"(?<=<td>)(.*?)(?=</td>)";
Regex rgx = new Regex(pattern);
foreach (Match m in rg