using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"((<(p|h3.*)>.*<\/(.*)>)|(<(ul.*)>[\s\S]*<\/(ul)>))";
string input = @"<h1>This is heading 1</h1>
<h2 style=""color: aqua"">This is heading 2</h2>
<h3>This is heading 3</h3>
<p>This is a paragraph.</p>
<p>This is another paragraph.</p>
<a href=""https://www.w3schools.com"">This is a link</a>
<ul>
<li>Coffee</li>
<li>Tea</li>
<li>Milk</li>
</ul>";
RegexOptions options = RegexOptions.Multiline;
foreach (Match m in Regex.Matches(input, pattern, options))
{
Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index);
}
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx