求一个c#正则表达式

            string input = "哈哈哈[怒]sdfsdf[怒]斯蒂芬金水电开发[怒][偷笑][偷笑][偷笑]提取[怒] 这些表情";
            Regex reg = new Regex(@"\[[^\]]+]");
            foreach(Match m in reg.Matches(input))
                Console.WriteLine(m.Value);

            string s = "哈哈哈[怒]sdfsdf[怒]斯蒂芬金水电开发[怒][偷笑][偷笑][偷笑]提取[怒] 这些表情";
            MatchCollection matches = Regex.Matches(s, @"(?<=\[).+?(?=\])");
            foreach (Match match in matches)
                Console.WriteLine(match.Value);
            Console.ReadKey();