using System;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
var input = @"<html>some text<coverpage><image l:href=""#cover.jpg""/></coverpage>some text</html>";
var pattern = @"<coverpage><image l:href=""#(.*?)""/></coverpage>";
Console.WriteLine(Regex.Match(input, pattern));
Console.WriteLine(Regex.Match(input, pattern).Groups[1]);
}
}
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