public static void Main()
<h1>This is <b>bold</b> heading</h1>
<p>This is <u>underlined</u> paragraph</p>
<h1>This is <i>italic</i> heading</h1>
<p>This is <u>underlined</u> paragraph</p>
var htmlDoc = new HtmlDocument();
var htmlNodes = htmlDoc.DocumentNode.SelectNodes("//body/h1");
foreach (var node in htmlNodes)
Console.WriteLine(node.InnerText);