Leetcode Regular Expression Matching problem solution in C#

public class Solution {
    public bool IsMatch(string s, string p) {
        // Handle the case where the pattern is empty.
        if (p.Length == 0)
        {
            return s.Length == 0;
        }

        // Handle the case where the pattern contains a single character.
        if (p.Length == 1 || p[1] != '*')
        {
            if (s.Length == 0 || (p[0] != '.' && p[0] != s[0]))
            {
                return false;
            }
            return IsMatch(s.Substring(1), p.Substring(1));
        }

        // Handle the case where the pattern contains multiple characters.
        int i = -1;
        while (i < s.Length && (i < 0 || p[0] == '.' || p[0] == s[i]))
        {
            if (IsMatch(s.Substring(i + 1), p.Substring(2)))
            {
                return true;
            }
            i++;
        }

        return false;
    }
}