using System.Text.RegularExpressions;
public static void Main()
string s = @"Welcome to the Center
Description about the course
Description about the course
Description about the course ";
var pattern = "(Batch #[0-9].*\n.*\n.*)";
Regex r = new Regex(pattern, RegexOptions.Multiline);
var myList = r.Matches(s);
foreach(var item in myList)