using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"<div\s+class=""asd""> # match an opening 'div' with an id that starts with 't' and some digits
[^<>]* # match zero or more chars other than '<' and '>'
( # open group 1
<div[^>]*> # match an opening 'div'
(?: # open a non-matching group
[^<>]* # match zero or more chars other than '<' and '>'
| # OR
(?1) # recursively match what is defined by group 1
)* # close the non-matching group and repeat it zero or more times
</div> # match a closing 'div'
) # close group 1
[^<>]* # match zero or more chars other than '<' and '>'
</div> ";
string input = @"<div>
<div class=""asd"">
<div>
<div>
Hello
</div>
</div>
</div>
</div>";
RegexOptions options = RegexOptions.Multiline | RegexOptions.Singleline | RegexOptions.IgnoreCase | RegexOptions.IgnorePatternWhitespace;
Match m = Regex.Match(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