using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"<li>(?>[^<]+|(<[uo]l)>|<(?!\/?li)[^>]*>|(?R))*<\/li>(?(1)|(*F))";
string input = @"<li>Hi</li> - Just some text, should ignore
<li><ul><li>hi</li></ul></li> - Directly in <li>
<li>Hi<ul><li>hi</li></ul></li> - Plain text before the nested list
<li><strong>Hi</strong><ul><li>hi</li></ul></li> - HTML content before the nested list
<ul><li>list item 1</li></ul>
<ul><li>list item 1</li><li><ol><li>2.1</li><li>2.2</li><li>2.3</li></ol></li><li>list item 3</li></ul>
<ul><li>list item 1</li><li>asdasdas<ol><li>2.1</li><li>2.2</li><li>2.3</li></ol></li><li>list item 3</li></ul>
<ul><li>list item 1</li><li><strong>asdasdas</strong><ol><li>2.1</li><li>2.2</li><li>2.3</li></ol></li><li>list item 3</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